What is a rare disease?
Rare diseases are diseases which affect a small number of people compared to the general population and specific issues are raised in relation to their rarity. In Europe, a disease is considered to be rare when it affects 1 person per 2000. A disease can be rare in one region, but common in another. This is the case of thalassemia, an anaemia of genetic origin, which is rare in Northern Europe, but it is frequent in the Mediterranean region. 'Periodic disease' is rare in France, but common in Armenia. There are also many common diseases whose variants are rare.

How many rare diseases are there?
There are thousands of rare diseases. To date, six to seven thousand rare diseases have been discovered and new diseases are regularly described in medical literature. The number of rare diseases also depends on the degree of specificity used when classifying the different entities/disorders. Until now, in the field of medicine, a disease is defined as an alteration of the state of health, presenting as a unique pattern of symptoms with a single treatment. Whether a pattern is considered unique depends entirely on the level of definition of our analysis. The more accurate our analysis, the more we notice certain nuances. This complexity is reflected in the various classifications provided by Orphanet.

What are the origins and characteristics of rare diseases?
While nearly all genetic diseases are rare diseases, not all rare diseases are genetic diseases. There are also very rare forms of infectious diseases, such as auto-immune diseases and rare cancers. To date, the cause remains unknown for many rare diseases.

Rare diseases are serious, often chronic and progressive, diseases. For many rare diseases, signs may be observed at birth or in childhood, as is the case of proximal spinal muscular atrophy, neurofibromatosis, osteogenesis imperfecta, chondrodysplasia or Rett syndrome. However, over 50% of rare diseases appear during adulthood, such as Huntington diseases, Crohn disease, Charcot-Marie-Tooth disease, amyotrophic lateral sclerosis, Kaposi's sarcoma or thyroid cancer.

What are the medical and social consequences of the rarity of these diseases?
The field of rare diseases suffers from a deficit of medical and scientific knowledge. For a long time, doctors, researchers and policy makers were unaware of rare diseases and until very recently there was no real research or public health policy concerning issues related to the field. There is no cure for most rare diseases, but the appropriate treatment and medical care can improve the quality of life of those affected and extend their life expectancy. Impressive progress has already been made for certain diseases, which shows that we must not give up the fight, but on the contrary, continue and step up efforts in the fields of research and social solidarity.

Those affected by these diseases all face similar difficulties in their quest for a diagnosis, relevant information and proper direction towards qualified professionals. Specific issues are equally raised regarding access to quality health care, overall social and medical support, effective liaison between hospitals and general practices, as well as professional and social integration and independence.

Those affected by rare diseases are also more psychologically, socially, economically and culturally vulnerable. These difficulties could be overcome by appropriate policies. Due to the lack of sufficient scientific and medical knowledge, many patients are not diagnosed and their disease remains unidentified. These are the people who suffer the most from difficulties in receiving appropriate support.

What progress is foreseen in the diagnosis and treatment of rare diseases?
For all rare diseases, science can provide some answers. Hundreds of rare diseases can now be diagnosed through a biological sample test. Knowledge of the natural history of these diseases is improved by the creation of registries. Researchers are increasingly working through networks in order to share the results of their research and to advance more efficiently. New hopes arise with the perspectives offered by European and national policies in many European countries in the field of rare diseases.

How can I obtain information about a specific disease?
Orphanet provides an inventory of rare diseases and related information for over 6000 of these diseases, as well as a directory of expert resources in the countries of the consortium.
https://www.orpha.net/consor/cgi-bin/Education_AboutRareDiseases.php?lng=EN

How can I obtain information about a specific CNS disease?
When most people think of neurological disorders, a small number of diseases that affect millions of people-such as epilepsy, Parkinson's disease, and stroke-come to mind. There are numerous rare diseases, which are defined as conditions affecting fewer than 200,000 Americans. In fact, due to the prevalence of neurological symptoms in rare diseases-of the estimated 7,000 known rare diseases that lead to significant morbidity and mortality in 25 million people in the United States, a third are thought to include a neurological rare diseases.

Examples of rare neurological conditions are amyotrophic lateral sclerosis (ALS), Duchenne muscular dystrophy, and Huntington's disease. In addition, there are hundreds of other rare diseases, including cerebrovascular diseases, neurometabolic disorders, neuromuscular and neurodegenerative disorders, movement disorders, epilepsies and episodic disorders, channelopathies, mitochondrial encephalopathies, and childhood developmental and/or genetic syndromes involving autism or intellectual disability. 

Nervous System Rare Diseases

12q14 microdeletion syndrome
15q13.3 microdeletion syndrome
15q24 microdeletion syndrome
2-methylbutyryl-CoA dehydrogenase deficiency
22q11.2 deletion syndrome
22q13.3 deletion syndrome
2q23.1 microdeletion syndrome
2q37 deletion syndrome
3-alpha hydroxyacyl-CoA dehydrogenase deficiency
3MC syndrome
48,XXXY syndrome
48,XYYY
49, XXXXY syndrome
5q14.3 microdeletion syndrome
6-pyruvoyl-tetrahydropterin synthase deficiency
Aarskog syndrome
Abetalipoproteinemia
ABri amyloidosis
Absence of septum pellucidum
Aceruloplasminemia
Acrocallosal syndrome, Schinzel type
Acrofacial dysostosis Catania type
Acrofacial dysostosis Rodriguez type
Acute cholinergic dysautonomia
Acute disseminated encephalomyelitis
Acute intermittent porphyria
ADCY5-related dyskinesia
Adenosine monophosphate deaminase 1 deficiency
Adenylosuccinase deficiency
Adie syndrome
Adrenomyeloneuropathy
Adult polyglucosan body disease
Adult-onset nemaline myopathy
Advanced sleep phase syndrome, familial
Agnosia
Aicardi syndrome
Aicardi-Goutieres syndrome
AIDS Dementia Complex
Al Gazali Aziz Salem syndrome
Alaninuria with microcephaly, dwarfism, enamel hypoplasia and diabetes mellitus
Albinism deafness syndrome
Alexander disease
ALG1-CDG (CDG-Ik)
ALG11-CDG (CDG-Ip)
ALG12-CDG (CDG-Ig)
ALG13-CDG
ALG2-CDG (CDG-Ii)
ALG3-CDG (CDG-Id)
ALG6-CDG (CDG-Ic)
ALG8-CDG (CDG-Ih)
ALG9-CDG (CDG-IL)
Allan-Herndon-Dudley syndrome
Alopecia epilepsy oligophrenia syndrome of Moynahan
Alopecia, epilepsy, pyorrhea, mental subnormality
Alopecia-contractures-dwarfism-intellectual disability syndrome
Alopecia-intellectual disability syndrome
Alpers syndrome
Alpha-ketoglutarate dehydrogenase deficiency
Alpha-mannosidosis
Alpha-thalassemia x-linked intellectual disability syndrome
Alternating hemiplegia of childhood
Alzheimer disease type 4 - See
Early-onset, autosomal dominant Alzheimer disease
Alzheimer's disease without neurofibrillary tangles
Aminoacylase 1 deficiency
Aminolevulinate dehydratase deficiency porphyria
Amish lethal microcephaly
Amish Nemaline Myopathy
Amyloid neuropathy
Amyopathic dermatomyositis
Amyotrophic lateral sclerosis
Amyotrophic lateral sclerosis type 6 - See
Amyotrophic lateral sclerosis
Amyotrophic lateral sclerosis-parkinsonism/dementia complex 1
Anaplastic astrocytoma
Anaplastic ganglioglioma
Anaplastic oligodendroglioma
Andermann syndrome
Andersen-Tawil syndrome
Anemia sideroblastic and spinocerebellar ataxia
Anencephaly
Angioma hereditary neurocutaneous
Aniridia - ptosis - intellectual disability - familial obesity
Aniridia renal agenesis psychomotor retardation
Antisynthetase syndrome
Aortic arch anomaly - peculiar facies - intellectual disability
Apraxia
Arachnoid cysts
Arachnoiditis
Aromatic L-amino acid decarboxylase deficiency
Arthrogryposis multiplex congenita, distal, X-linked
Arthrogryposis renal dysfunction cholestasis syndrome
Arthrogryposis, ectodermal dysplasia, cleft lip/palate, and developmental delay
Arts syndrome
Aspartylglycosaminuria
Ataxia - hypogonadism - choroidal dystrophy
Ataxia telangiectasia
Ataxia with oculomotor apraxia type 1
Ataxia with Oculomotor Apraxia Type 2
Ataxia with oculomotor apraxia type 4
Ataxia with vitamin E deficiency
Atelosteogenesis type 2
Atelosteogenesis type 3
Atkin syndrome
Atypical Rett syndrome
Autism with port-wine stain
Autosomal dominant centronuclear myopathy
Autosomal dominant cerebellar ataxia, deafness, and narcolepsy
Autosomal dominant Charcot-Marie-Tooth disease type 2 with giant axons
Autosomal dominant deafness-onychodystrophy syndrome
Autosomal dominant intermediate Charcot-Marie-Tooth disease type A - See
Autosomal dominant intermediate Charcot-Marie-Tooth
Autosomal dominant intermediate Charcot-Marie-Tooth disease type B - See
Autosomal dominant intermediate Charcot-Marie-Tooth
Autosomal dominant intermediate Charcot-Marie-Tooth disease type C - See
Autosomal dominant intermediate Charcot-Marie-Tooth
Autosomal dominant intermediate Charcot-Marie-Tooth disease type D - See
Autosomal dominant intermediate Charcot-Marie-Tooth
Autosomal dominant intermediate Charcot-Marie-Tooth disease type E - See
Autosomal dominant intermediate Charcot-Marie-Tooth
Autosomal dominant intermediate Charcot-Marie-Tooth disease type F - See
Autosomal dominant intermediate Charcot-Marie-Tooth
Autosomal dominant leukodystrophy with autonomic disease
Autosomal dominant neuronal ceroid lipofuscinosis 4B
Autosomal dominant nocturnal frontal lobe epilepsy
Autosomal dominant non-syndromic intellectual disability
Autosomal dominant optic atrophy plus syndrome
Autosomal dominant partial epilepsy with auditory features
Autosomal dominant spinal muscular atrophy, lower extremity-predominant 1
Autosomal recessive axonal neuropathy with neuromyotonia
Autosomal recessive centronuclear myopathy
Autosomal recessive Charcot-Marie-Tooth disease with hoarseness
Autosomal recessive intermediate Charcot-Marie-Tooth disease type A - See
Autosomal recessive intermediate Charcot-Marie-Tooth disease
Autosomal recessive intermediate Charcot-Marie-Tooth disease type B - See
Autosomal recessive intermediate Charcot-Marie-Tooth disease
Autosomal recessive juvenile Parkinson disease
Autosomal recessive neuronal ceroid lipofuscinosis 4A - See
Adult neuronal ceroid lipofuscinosis
Autosomal recessive primary microcephaly
Autosomal recessive spastic ataxia 4
Autosomal recessive spastic paraplegia type 49
Autosomal recessive spinocerebellar ataxia 9
B4GALT1-CDG (CDG-IId)
Bannayan-Riley-Ruvalcaba syndrome
Barth syndrome
Battaglia-Neri syndrome
Becker muscular dystrophy
Behavioral variant of frontotemporal dementia
Behçet disease
Bell's palsy
Benign essential blepharospasm
Benign familial neonatal epilepsy
Benign familial neonatal-infantile seizures
Benign hereditary chorea
Benign rolandic epilepsy (BRE)
Beta-Propeller Protein-Associated Neurodegeneration
Bethlem myopathy
Bilateral frontal polymicrogyria
Bilateral frontoparietal polymicrogyria
Bilateral generalized polymicrogyria
Bilateral parasagittal parieto-occipital polymicrogyria
Bilateral perisylvian polymicrogyria
Binswanger's disease
Biotin-thiamine-responsive basal ganglia disease
Biotinidase deficiency
Birk-Barel syndrome
Bixler Christian Gorlin syndrome
Blepharonasofacial malformation syndrome
Bobble-head doll syndrome
Bohring-Opitz syndrome
Borjeson-Forssman-Lehmann syndrome
Bowen-Conradi syndrome
Brachioskeletogenital syndrome
Brachydactyly-mesomelia-intellectual disability-heart defects syndrome
Brain dopamine-serotonin vesicular transport disease
Brain-lung-thyroid syndrome
Branchial arch syndrome X-linked
Brody myopathy
Brooks Wisniewski Brown syndrome
Brown-Sequard syndrome
Bullous dystrophy hereditary macular type
C syndrome
Cabezas syndrome
CADASIL
Camptocormism
Camptodactyly arthropathy coxa vara pericarditis syndrome
CANOMAD syndrome
Cantu syndrome
Cap myopathy
Cardiofaciocutaneous syndrome
Carey-Fineman-Ziter syndrome
Carney complex
Cataract ataxia deafness
Catel Manzke syndrome
Caudal appendage deafness
Caudal regression sequence
Central core disease
Central nervous system germinoma
Central neurocytoma
Central pain syndrome
Central pontine myelinolysis - Not a rare disease
Cerebellar ataxia and hypogonadotropic hypogonadism
Cerebellar ataxia, areflexia, pes cavus, optic atrophy and sensorinural hearing loss
Cerebellar degeneration
Cerebellar hypoplasia
Cerebellar hypoplasia tapetoretinal degeneration
Cerebellar hypoplasia with endosteal sclerosis
Cerebelloparenchymal disorder 3
Cerebellum agenesis hydrocephaly
Cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy
Cerebral cavernous malformation - Not a rare disease
Cerebral dysgenesis, neuropathy, ichthyosis, and palmoplantar keratoderma syndrome
Cerebral folate deficiency
Cerebral gigantism jaw cysts
Cerebral palsy - Not a rare disease
Cerebral palsy ataxic
Cerebral palsy athetoid
Cerebral palsy spastic hemiplegic
Cerebral palsy spastic monoplegic
Cerebral palsy spastic quadriplegic
Cerebral sclerosis similar to Pelizaeus-Merzbacher disease
Cerebro-facio-articular syndrome
Cerebro-oculo-facio-skeletal syndrome
Cerebrooculonasal syndrome
Cerebrospinal fluid leak
Cerebrotendinous xanthomatosis
Ceroid lipofuscinosis neuronal 1
Cervical hypertrichosis peripheral neuropathy
Chanarin-Dorfman syndrome
Charcot-Marie-Tooth disease
Charcot-Marie-Tooth disease type 1A
Charcot-Marie-Tooth disease type 1B - See
Charcot-Marie-Tooth disease
Charcot-Marie-Tooth disease type 1C - See
Charcot-Marie-Tooth disease
Charcot-Marie-Tooth disease type 1D - See
Charcot-Marie-Tooth disease
Charcot-Marie-Tooth disease type 1E
Charcot-Marie-Tooth disease type 1F - See
Charcot-Marie-Tooth disease
Charcot-Marie-Tooth disease type 2B
Charcot-Marie-Tooth disease type 2B1 - See
Charcot-Marie-Tooth disease
Charcot-Marie-Tooth disease type 2B2 - See
Charcot-Marie-Tooth disease
Charcot-Marie-Tooth disease type 2D - See
Charcot-Marie-Tooth disease
Charcot-Marie-Tooth disease type 2E - See
Charcot-Marie-Tooth disease
Charcot-Marie-Tooth disease type 2F
Charcot-Marie-Tooth disease type 2G - See
Charcot-Marie-Tooth disease
Charcot-Marie-Tooth disease type 2H - See
Charcot-Marie-Tooth disease
Charcot-Marie-Tooth disease type 2I - See
Charcot-Marie-Tooth disease
Charcot-Marie-Tooth disease type 2J - See
Charcot-Marie-Tooth disease
Charcot-Marie-Tooth disease type 2K - See
Charcot-Marie-Tooth disease
Charcot-Marie-Tooth disease type 2N - See
Charcot-Marie-Tooth disease
Charcot-Marie-Tooth disease type 2O - See
Charcot-Marie-Tooth disease
Charcot-Marie-Tooth disease type 2P
Charcot-Marie-Tooth disease type 2Q - See
Charcot-Marie-Tooth disease
Charcot-Marie-Tooth disease type 2R
Charcot-Marie-Tooth disease type 4A - See
Charcot-Marie-Tooth disease
Charcot-Marie-Tooth disease type 4B1 - See
Charcot-Marie-Tooth disease
Charcot-Marie-Tooth disease type 4B2
Charcot-Marie-Tooth disease type 4C - See Charcot-Marie-Tooth disease
Charcot-Marie-Tooth disease type 4D - See
Charcot-Marie-Tooth disease
Charcot-Marie-Tooth disease type 4E - See
Charcot-Marie-Tooth disease
Charcot-Marie-Tooth disease type 4H - See
Charcot-Marie-Tooth disease
Chediak-Higashi syndrome
Chiari malformation - Not a rare disease
Chiari malformation type 1 - Not a rare disease
Chiari malformation type 2
Chiari malformation type 4
Childhood apraxia of speech
Childhood-onset nemaline myopathy
Chorea-acanthocytosis
Choroid plexus carcinoma
Choroid plexus papilloma
Christianson syndrome
Chromosome 17p13.1 deletion syndrome
Chromosome 17q11.2 deletion syndrome
Chromosome 19q13.11 deletion syndrome
Chromosome 1p36 deletion syndrome
Chromosome 3p- syndrome
Chronic hiccups
Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids
Chronic progressive external ophthalmoplegia
Chudley Rozdilsky syndrome
Cleft palate short stature vertebral anomalies
Cluster headache - Not a rare disease
COACH syndrome
COASY Protein-Associated Neurodegeneration
Coats disease
Cobb syndrome
Cockayne syndrome type I
Cockayne syndrome type II
Cockayne syndrome type III
Coenzyme Q10 deficiency
Coffin-Lowry syndrome
Coffin-Siris syndrome
COG1-CDG (CDG-IIg)
COG4-CDG (CDG-IIj)
COG5-CDG (CDG-IIi)
COG7-CDG (CDG-IIe)
COG8-CDG (CDG-IIh)
Cohen syndrome
Cold-induced sweating syndrome
Complex regional pain syndrome
Congenital central hypoventilation syndrome
Congenital cytomegalovirus
Congenital fiber type disproportion
Congenital fibrosis of extraocular muscles
Congenital generalized lipodystrophy type 4
Congenital insensitivity to pain
Congenital insensitivity to pain with anhidrosis
Congenital intrauterine infection-like syndrome
Congenital laryngeal palsy
Congenital mirror movement disorder
Congenital muscular dystrophy due to LMNA mutation - See Congenital muscular dystrophy
Congenital muscular dystrophy type 1A
Congenital muscular dystrophy with integrin alpha-7 deficiency - See
Congenital muscular dystrophy
Congenital muscular dystrophy-dystroglycanopathy with or without intellectual disability (type B)
Congenital myasthenic syndrome with episodic apnea
Congenital rubella
Congenital toxoplasmosis - Not a rare disease
Continuous spike-wave during slow sleep syndrome
Convulsions, benign familial infantile, 1
Corneal hypesthesia, familial
Cornelia de Lange syndrome
Corpus callosum agenesis double urinary collecting
Cortical blindness-intellectual disability-polydactyly syndrome
Cortical dysgenesis with pontocerebellar hypoplasia due to TUBB3 mutation
Corticobasal degeneration
Costello syndrome
Crane-Heise syndrome
Craniofrontonasal dysplasia
Craniopharyngioma
Craniorachischisis
Craniotelencephalic dysplasia
Creutzfeldt-Jakob disease
Crome syndrome
Curry Jones syndrome
Cylindrical spirals myopathy
Cyprus facial neuromusculoskeletal syndrome
Cytomegalic inclusion disease
D-2-hydroxyglutaric aciduria
Dandy-Walker cyst with Renal-Hepatic-Pancreatic dysplasia
Dandy-Walker like malformation with atrioventricular septal defect
Dandy-Walker malformation with intellectual disability, basal ganglia disease and seizures
Dandy-Walker malformation with postaxial polydactyly
Dandy-Walker malformation with sagittal craniosynostosis and hydrocephalus
Danon disease
DDOST-CDG (CDG-Ir)
DEAF1-associated disorders
Deafness, dystonia, and cerebral hypomyelination
Dentatorubral-pallidoluysian atrophy
Dermatomyositis
Developmental dysphasia familial
Dihydrolipoamide dehydrogenase deficiency
Dihydropteridine reductase deficiency
Distal myopathy with vocal cord weakness
DOOR syndrome
Dopa-responsive dystonia
Dopamine beta hydroxylase deficiency
Dopamine transporter deficiency syndrome
DPAGT1-CDG (CDG-Ij)
DPM1-CDG (CDG-Ie)
DPM2-CDG
DPM3-CDG (CDG-Io)
Dravet syndrome
Duane syndrome
Dubowitz syndrome
Duchenne muscular dystrophy
Dykes Markes Harper syndrome
Dysautonomia like disorder
Dysequilibrium syndrome
Dyskeratosis congenita
Dyskeratosis congenita autosomal dominant
Dyskeratosis congenita autosomal recessive
Dyskeratosis congenita X-linked
Dyssynergia cerebellaris myoclonica
Dystonia 2, torsion, autosomal recessive
DYT-PRKRA
DYT-THAP1
DYT-TOR1A
DYT-TUBB4A
Early Infantile Epileptic Encephalopathy
Early infantile epileptic encephalopathy 25
Early-onset anterior polar cataract
Early-onset parkinsonism-intellectual disability syndrome
Early-onset, autosomal dominant Alzheimer disease
Eastern equine encephalitis
Empty sella syndrome
Encephalitis lethargica
Encephalocraniocutaneous lipomatosis
Encephalopathy due to prosaposin deficiency - See
Sphingolipidosis
Eosinophilic fasciitis
Eosinophilic granulomatosis with polyangiitis
Ependymoma
Epidermolysa bullosa simplex with muscular dystrophy
Epilepsy juvenile absence
Epilepsy occipital calcifications
Epilepsy progressive myoclonic type 3
Epilepsy with myoclonic-atonic seizures
Epiphyseal dysplasia hearing loss dysmorphism
Episodic ataxia
Episodic ataxia with nystagmus
Erythromelalgia
Essential tremor - Not a rare disease
Fabry disease
Facial onset sensory and motor neuronopathy
Facioscapulohumeral muscular dystrophy
Fallot complex with severe mental and growth retardation
Familial amyloidosis, Finnish type
Familial bilateral striatal necrosis
Familial caudal dysgenesis
Familial congenital palsy of trochlear nerve
Familial dysautonomia
Familial encephalopathy with neuroserpin inclusion bodies
Familial exudative vitreoretinopathy
Familial focal epilepsy with variable foci
Familial hemiplegic migraine
Familial hemophagocytic lymphohistiocytosis
Familial infantile convulsions and paroxysmal choreoathetosis
Familial porencephaly
Familial transthyretin amyloidosis
Familiar or sporadic hemiplegic migraine
Farber disease
Fatal familial insomnia
Fatal infantile encephalomyopathy
Fatty acid hydroxylase-associated neurodegeneration
FBXL4-related encephalomyopathic mitochondrial DNA depletion syndrome
Febrile infection-related epilepsy syndrome
Feigenbaum Bergeron Richardson syndrome
Filippi syndrome
Fine-Lubinsky syndrome
Fingerprint body myopathy
Fitzsimmons Walson Mellor syndrome
Fitzsimmons-Guilbert syndrome
Floating-Harbor syndrome
Flynn Aird syndrome
Focal dermal hypoplasia
Focal segmental glomerulosclerosis
Fountain syndrome
FOXG1 syndrome
Fragile X syndrome
Fragile XE syndrome
Friedreich ataxia
Frontometaphyseal dysplasia
Frontotemporal dementia
Fryns syndrome
Fucosidosis
Fukuyama type muscular dystrophy
Fumarase deficiency
Galactosialidosis
Galloway-Mowat syndrome
Gamma aminobutyric acid transaminase deficiency
Gangliocytoma
GAPO syndrome
Gaucher disease type 1
Gaucher disease type 2
Gaucher disease type 3
Gemignani syndrome
Genitopatellar syndrome
Genoa syndrome
Gerstmann syndrome
Gerstmann-Straussler-Scheinker disease
Giant axonal neuropathy
Gillespie syndrome
Gliomatosis cerebri
Glucose transporter type 1 deficiency syndrome
Glutamine deficiency, congenital
Glutaric acidemia type I
Glutaric acidemia type II
Glutaric acidemia type III
Glycogen storage disease type 13
Glycogen storage disease type 2
Glycogen storage disease type 3
Glycogen storage disease type 4
Glycogen storage disease type 5
Glycogen storage disease type 7
GM1 gangliosidosis type 1
GM1 gangliosidosis type 2
GM1 gangliosidosis type 3
GM3 synthase deficiency
GMS syndrome
Goldberg-Shprintzen megacolon syndrome
Gomez Lopez Hernandez syndrome
GOSR2-related progressive myoclonus ataxia
Graham-Cox syndrome
Granulomatosis with polyangiitis
Griscelli syndrome type 1
Grubben de Cock Borghgraef syndrome
GTP cyclohydrolase I deficiency
GTPCH1-deficient DRD
Guanidinoacetate methyltransferase deficiency
Guillain-Barre syndrome
Gurrieri syndrome
Gyrate atrophy of choroid and retina
Hair defect-photosensitivity-intellectual disability syndrome
Hall-Riggs syndrome
Hallermann-Streiff syndrome
Hamanishi Ueba Tsuji syndrome
Hansen's disease
Harding ataxia
Harlequin syndrome
Harrod Doman Keele syndrome
Hartnup disease
Hashimoto encephalopathy
Hemangioblastoma
Hemicrania continua
Hemimegalencephaly
Hennekam syndrome
Hereditary angiopathy with nephropathy, aneurysms, and muscle cramps syndrome
Hereditary coproporphyria
Hereditary diffuse leukoencephalopathy with spheroids
Hereditary fibrosing poikiloderma with tendon contractures, myopathy, and pulmonary fibrosis
Hereditary geniospasm
Hereditary hemorrhagic telangiectasia
Hereditary hemorrhagic telangiectasia type 2
Hereditary hemorrhagic telangiectasia type 3
Hereditary hemorrhagic telangiectasia type 4
Hereditary hyperekplexia
Hereditary motor and sensory neuropathy type 5
Hereditary neuropathy with liability to pressure palsies
Hereditary proximal myopathy with early respiratory failure
Hereditary sensorimotor neuropathy with hyperelastic skin
Hereditary sensory and autonomic neuropathy type 1E
Hereditary sensory and autonomic neuropathy type 2
Hereditary sensory and autonomic neuropathy type 7
Hereditary sensory and autonomic neuropathy type V
Hereditary sensory neuropathy type 1
Hereditary spastic paraplegia
Hereditary vascular retinopathy
Hernández-Aguirre Negrete syndrome
Herpes simplex encephalitis
Herpes zoster oticus
HIBCH deficiency
Homocystinuria due to CBS deficiency
Homocystinuria due to MTHFR deficiency
Horizontal gaze palsy with progressive scoliosis
Hoyeraal Hreidarsson syndrome
HSD10 disease
HTLV-1 associated myelopathy/tropical spastic paraparesis
Human HOXA1 Syndromes
Huntington disease
Hurler syndrome
Hurler–Scheie syndrome
Hydranencephaly
Hydrocephalus due to congenital stenosis of aqueduct of sylvius
Hydrocephalus-cleft palate-joint contractures syndrome
Hydroxykynureninuria
Hyperbetaalaninemia
Hypercoagulability syndrome due to glycosylphosphatidylinositol deficiency
Hyperkalemic periodic paralysis
Hypermethioninemia due to S-adenosylhomocysteine hydrolase deficiency
Hyperphenylalaninemia due to dehydratase deficiency
Hyperprolinemia
Hyperprolinemia type 2
Hypertrophic neuropathy of Dejerine-Sottas
Hypocalcemia, autosomal dominant
Hypokalemic periodic paralysis
Hypomelanosis of Ito
Hypomyelination and congenital cataract
Hypomyelination with atrophy of basal ganglia and cerebellum
Hypoparathyroidism-intellectual disability-dysmorphism syndrome
Hypospadias-intellectual disability, Goldblatt type syndrome
Hypothalamic hamartomas
Ichthyosis alopecia eclabion ectropion mental retardation
Idiopathic intracranial hypertension
Idiopathic spinal cord herniation
Inclusion body myopathy 2
Inclusion body myopathy 3
Inclusion body myopathy with early-onset Paget disease and frontotemporal dementia
Inclusion body myositis
Incontinentia pigmenti
Infantile axonal neuropathy
Infantile cerebellar retinal degeneration
Infantile choroidocerebral calcification syndrome
Infantile myofibromatosis
Infantile neuroaxonal dystrophy
Infantile onset spinocerebellar ataxia
Infantile spasms broad thumbs
Infantile-onset ascending hereditary spastic paralysis
Infection-induced acute encephalopathy 3
Intellectual deficit - short stature - hypertelorism
Intellectual deficit Buenos-Aires type
Intellectual disability - athetosis - microphthalmia
Intellectual disability - hypoplastic corpus callosum - preauricular tag
Intellectual disability-developmental delay-contractures syndrome
Intellectual disability-dysmorphism-hypogonadism-diabetes mellitus syndrome
Intellectual disability-severe speech delay-mild dysmorphism syndrome
Intellectual disability-spasticity-ectrodactyly syndrome
Intermediate congenital nemaline myopathy
Internal carotid agenesis
Intraneural perineurioma
IRVAN syndrome
Isaacs' syndrome
Isodicentric chromosome 15 syndrome
Johanson-Blizzard syndrome
Johnson neuroectodermal syndrome
Joubert syndrome
Joubert syndrome with oculorenal anomalies
Juberg Marsidi syndrome
Juvenile amyotrophic lateral sclerosis
Juvenile dermatomyositis
Juvenile Huntington disease
Juvenile polymyositis
Juvenile primary lateral sclerosis
Kabuki syndrome
Kanzaki disease
Kapur Toriello syndrome
Kaufman oculocerebrofacial syndrome
KBG syndrome
KCNQ2-Related Disorders
Kearns-Sayre syndrome
Kennedy disease
Keratosis follicularis dwarfism and cerebral atrophy
Kernicterus
Keutel syndrome
King Denborough syndrome
Kleine Levin syndrome
Klumpke paralysis
Kosztolanyi syndrome
Kozlowski-Krajewska syndrome
Kuru
Kuzniecky Andermann syndrome
L-2-hydroxyglutaric aciduria
L-arginine:glycine amidinotransferase deficiency
La Crosse encephalitis
Laband syndrome
Lafora disease
Laing distal myopathy
Lambert Eaton myasthenic syndrome
Landau-Kleffner syndrome
Late-onset distal myopathy, Markesbery-Griggs type
Lateral meningocele syndrome
Laurence-Moon syndrome
LCHAD deficiency
Leber hereditary optic neuropathy with dystonia
Leigh syndrome, French Canadian type
Lennox-Gastaut syndrome
Lenz Majewski hyperostotic dwarfism
Lenz microphthalmia syndrome
Lesch Nyhan syndrome
Leukodystrophy
Leukodystrophy, dysmyelinating, and spastic paraparesis with or without dystonia
Leukoencephalopathy - dystonia - motor neuropathy
Leukoencephalopathy with brain stem and spinal cord involvement and lactate elevation
Leukoencephalopathy with thalamus and brainstem involvement and high lactate
Levic Stefanovic Nikolic syndrome
Lewis-Sumner syndrome
Lhermitte-Duclos disease
Li-Fraumeni syndrome
Limb-girdle muscular dystrophy type 1A
Limb-girdle muscular dystrophy type 1B
Limb-girdle muscular dystrophy type 1C - See
Limb-girdle muscular dystrophy
Limb-girdle muscular dystrophy type 1D - See
Limb-girdle muscular dystrophy
Limb-girdle muscular dystrophy type 1E - See
Limb-girdle muscular dystrophy
Limb-girdle muscular dystrophy type 1F - See
Limb-girdle muscular dystrophy
Limb-girdle muscular dystrophy type 1G - See
Limb-girdle muscular dystrophy
Limb-girdle muscular dystrophy type 1H - See
Limb-girdle muscular dystrophy
Limb-girdle muscular dystrophy type 2A
Limb-girdle muscular dystrophy type 2B
Limb-girdle muscular dystrophy type 2E
Limb-girdle muscular dystrophy type 2F
Limb-girdle muscular dystrophy type 2H
Limb-girdle muscular dystrophy type 2I
Limb-girdle muscular dystrophy type 2J - See
Limb-girdle muscular dystrophy
Limb-girdle muscular dystrophy type 2K - See
Limb-girdle muscular dystrophy
Limb-girdle muscular dystrophy type 2L - See
Limb-girdle muscular dystrophy
Limb-girdle muscular dystrophy type 2M - See
Limb-girdle muscular dystrophy
Limb-girdle muscular dystrophy type 2N - See
Limb-girdle muscular dystrophy
Limb-girdle muscular dystrophy type 2O - See
Limb-girdle muscular dystrophy
Limb-girdle muscular dystrophy type 2P - See
Limb-girdle muscular dystrophy type 1A
Limb-girdle muscular dystrophy type 2Q - See
Limb-girdle muscular dystrophy
Limb-girdle muscular dystrophy type 2S - See
Limb-girdle muscular dystrophy
Limb-girdle muscular dystrophy type 2T - See
Limb-girdle muscular dystrophy
Limb-girdle muscular dystrophy, type 2C
Limb-girdle muscular dystrophy, type 2D
Limb-girdle muscular dystrophy, type 2G
Limbic encephalitis with LGI1 antibodies
Limited cutaneous systemic sclerosis
Lipoic acid synthetase deficiency
Lissencephaly 1
Lissencephaly 2
Lissencephaly X-linked
Localized hypertrophic neuropathy
Locked-in syndrome
Logopenic progressive aphasia
Lowe oculocerebrorenal syndrome
Lowry Maclean syndrome
Lujan syndrome
Lyme disease - Not a rare disease
Mac Dermot Winter syndrome
Macrocephaly-short stature-paraplegia syndrome
Macrothrombocytopenia progressive deafness
Mal de debarquement syndrome
Male pseudohermaphroditism intellectual disability syndrome, Verloes type
Malignant hyperthermia
Malignant hyperthermia arthrogryposis torticollis
Malignant migrating partial seizures of infancy
MAN1B1-CDG
Mandibulofacial dysostosis with microcephaly
Mannosidosis, beta A, lysosomal
Marchiafava Bignami disease
Marden-Walker syndrome
Marfanoid habitus-autosomal recessive intellectual disability syndrome
Marinesco-Sjogren syndrome
Martsolf syndrome
McDonough syndrome
McLeod neuroacanthocytosis syndrome
Meckel syndrome
MECP2 duplication syndrome
Medrano Roldan syndrome
Medulloblastoma
Megalencephalic leukoencephalopathy with subcortical cysts
Megalencephaly-Polymicrogyria-Polydactyly-Hydrocephalus syndrome
Megaloblastic anemia due to dihydrofolate reductase deficiency
Megalocornea-intellectual disability syndrome
Mehes syndrome
MEHMO syndrome
Meier-Gorlin syndrome
Meige syndrome
Melnick-Needles syndrome
Meningioma
Menkes disease
Mental retardation skeletal dysplasia abducens palsy
Mental retardation X-linked syndromic 7
Meralgia paresthetica
Metaphyseal dysostosis-intellectual disability-conductive deafness syndrome
Methionine adenosyltransferase deficiency
Methylcobalamin deficiency cbl G type
Methylmalonic acidemia with homocystinuria type cblC - See
Methylmalonic acidemia with homocystinuria
MGAT2-CDG (CDG-IIa)
Micro syndrome
Microbrachycephaly ptosis cleft lip
Microcephalic osteodysplastic primordial dwarfism type 1
Microcephalic osteodysplastic primordial dwarfism type 2
Microcephalic primordial dwarfism Toriello type
Microcephalic primordial dwarfism, Montreal type
Microcephaly
Microcephaly autosomal dominant
Microcephaly brain defect spasticity hypernatremia
Microcephaly cervical spine fusion anomalies
Microcephaly deafness syndrome
Microcephaly glomerulonephritis Marfanoid habitus
Microcephaly microcornea syndrome Seemanova type
Microcephaly, seizures, and developmental delay - See
Early Infantile Epileptic Encephalopathy
Microcephaly-cardiomyopathy
Microduplication Xp11.22-p11.23 syndrome
Microphthalmia syndromic 10
Microphthalmia syndromic 4
Microphthalmia syndromic 8
Microphthalmia with linear skin defects syndrome
Microscopic polyangiitis
Migraine with brainstem aura
Mild phenylketonuria
Miller-Dieker syndrome
Miller-Fisher syndrome
Minicore myopathy with external ophthalmoplegia
Mitochondrial complex I deficiency
Mitochondrial complex II deficiency
Mitochondrial DNA depletion syndrome, encephalomyopathic form with methylmalonic aciduria
Mitochondrial DNA-associated Leigh syndrome
Mitochondrial encephalomyopathy lactic acidosis and stroke-like episodes
Mitochondrial Membrane Protein-Associated Neurodegeneration
Mitochondrial myopathy and sideroblastic anemia
Mitochondrial myopathy with diabetes
Mitochondrial myopathy with lactic acidosis
Mitochondrial neurogastrointestinal encephalopathy syndrome
Mitochondrial trifunctional protein deficiency
Mixed connective tissue disease
Miyoshi myopathy
Moebius syndrome
MOGS-CDG (CDG-IIb)
Mohr-Tranebjaerg syndrome
Molybdenum cofactor deficiency
Monoamine oxidase A deficiency
Morse-Rawnsley-Sargent syndrome
Morvan's fibrillary chorea
Mousa Al din Al Nassar syndrome
Moyamoya disease
MPDU1-CDG (CDG-If)
MPI-CDG (CDG-Ib)
MPV17-related hepatocerebral mitochondrial DNA depletion syndrome
Mucolipidosis type 4
Mucopolysaccharidosis type III
Mucopolysaccharidosis type IIIA
Mucopolysaccharidosis type IIIB
Mucopolysaccharidosis type IIIC
Mucopolysaccharidosis type IIID
Multifocal motor neuropathy
Multiple congenital anomalies-hypotonia-seizures syndrome
Multiple congenital anomalies-hypotonia-seizures syndrome type 2
Multiple myeloma
Multiple sulfatase deficiency
Multiple system atrophy
Multisystemic smooth muscle dysfunction syndrome
Muscle eye brain disease
Muscular dystrophy white matter spongiosis
Muscular dystrophy, congenital, megaconial type
Muscular phosphorylase kinase deficiency
Musculocontractural Ehlers-Danlos syndrome
Myasthenia gravis
Myelocerebellar disorder
Myelomeningocele

Microphthalmia syndromic 8
Microphthalmia with linear skin defects syndrome
Microscopic polyangiitis
Migraine with brainstem aura
Mild phenylketonuria
Miller-Dieker syndrome
Miller-Fisher syndrome
Minicore myopathy with external ophthalmoplegia
Mitochondrial complex I deficiency
Mitochondrial complex II deficiency
Mitochondrial DNA depletion syndrome, encephalomyopathic form with methylmalonic aciduria
Mitochondrial DNA-associated Leigh syndrome
Mitochondrial encephalomyopathy lactic acidosis and stroke-like episodes
Mitochondrial Membrane Protein-Associated Neurodegeneration
Mitochondrial myopathy and sideroblastic anemia
Mitochondrial myopathy with diabetes
Mitochondrial myopathy with lactic acidosis
Mitochondrial neurogastrointestinal encephalopathy syndrome
Mitochondrial trifunctional protein deficiency
Mixed connective tissue disease
Miyoshi myopathy
Moebius syndrome
MOGS-CDG (CDG-IIb)
Mohr-Tranebjaerg syndrome
Molybdenum cofactor deficiency
Monoamine oxidase A deficiency
Morse-Rawnsley-Sargent syndrome
Morvan's fibrillary chorea
Mousa Al din Al Nassar syndrome
Moyamoya disease
MPDU1-CDG (CDG-If)
MPI-CDG (CDG-Ib)
MPV17-related hepatocerebral mitochondrial DNA depletion syndrome
Mucolipidosis type 4
Mucopolysaccharidosis type III
Mucopolysaccharidosis type IIIA
Mucopolysaccharidosis type IIIB
Mucopolysaccharidosis type IIIC
Mucopolysaccharidosis type IIID
Multifocal motor neuropathy
Multiple congenital anomalies-hypotonia-seizures syndrome
Multiple congenital anomalies-hypotonia-seizures syndrome type 2
Multiple myeloma
Multiple sulfatase deficiency
Multiple system atrophy
Multisystemic smooth muscle dysfunction syndrome
Muscle eye brain disease
Muscular dystrophy white matter spongiosis
Muscular dystrophy, congenital, megaconial type
Muscular phosphorylase kinase deficiency
Musculocontractural Ehlers-Danlos syndrome
Myasthenia gravis
Myelocerebellar disorder
Myelomeningocele
MYH7-related scapuloperoneal myopathy
Myhre syndrome
Myoclonic epilepsy with ragged red fibers
Myoclonus cerebellar ataxia deafness
Myoclonus-dystonia
Myoglobinuria recurrent
Myopathy with extrapyramidal signs
Myosin storage myopathy
Myotonia congenita
Myotonic dystrophy type 1
Myotonic dystrophy type 2
N syndrome
Nance-Horan syndrome
Narcolepsy
NBIA/DYT/PARK-PLA2G6
Necrotizing autoimmune myopathy
Neonatal adrenoleukodystrophy
Neonatal meningitis
Neonatal progeroid syndrome
Neu Laxova syndrome
Neuroblastoma
Neurocutaneous melanosis
Neurofaciodigitorenal syndrome
Neuroferritinopathy
Neurofibromatosis type 1
Neurofibromatosis type 2
Neuroleptic malignant syndrome
Neuromyelitis optica spectrum disorder
Neuronal ceroid lipofuscinosis
Neuronal ceroid lipofuscinosis 10
Neuronal ceroid lipofuscinosis 2
Neuronal ceroid lipofuscinosis 3
Neuronal ceroid lipofuscinosis 5
Neuronal ceroid lipofuscinosis 6
Neuronal ceroid lipofuscinosis 7
Neuronal ceroid lipofuscinosis 9
Neuronal intranuclear inclusion disease
Neuropathy ataxia retinitis pigmentosa syndrome
Neuropathy, distal hereditary motor, Jerash type
Neuropathy, hereditary motor and sensory, Okinawa type
Neuropathy, hereditary motor and sensory, Russe type
Neutral lipid storage disease with myopathy
Nevoid basal cell carcinoma syndrome
New-onset refractory status epilepticus
Nicolaides-Baraitser syndrome
Niemann-Pick disease type A
Niemann-Pick disease type B
Niemann-Pick disease type C1
Niemann-Pick disease type C2
Non 24 hour sleep wake disorder
Nondystrophic myotonia
Noonan syndrome
Norrie disease
Northern epilepsy
Oculocerebrocutaneous syndrome
Oculofaciocardiodental syndrome
Oculopharyngeal muscular dystrophy
Oculopharyngodistal myopathy
Okamoto syndrome
Olfactory neuroblastoma
Oligoastrocytoma
Oligodendroglioma
Oliver syndrome
Olivopontocerebellar atrophy
Omphalocele cleft palate syndrome lethal
OPHN1 syndrome
Opsoclonus-myoclonus syndrome
Optic atrophy 2
Optic pathway glioma
Ornithine transcarbamylase deficiency
Orofaciodigital syndrome 1
Orofaciodigital syndrome 10
Orofaciodigital syndrome 2
Orofaciodigital syndrome 3
Orofaciodigital syndrome 4
Orofaciodigital syndrome 5
Orofaciodigital syndrome 6
Orthostatic intolerance due to NET deficiency
Osteopenia and sparse hair
Osteoporosis-pseudoglioma syndrome
Oto-palato-digital syndrome type 1
Oto-palato-digital syndrome type 2
Ouvrier Billson syndrome
Pachygyria-intellectual disability-epilepsy syndrome
PACS1-related syndrome
Painful orbital and systemic neurofibromas-marfanoid habitus syndrome
Pallidopyramidal syndrome
Pallister W syndrome
Pallister-Killian mosaic syndrome
Pantothenate kinase-associated neurodegeneration
Paralysis agitans, juvenile, of Hunt
Paramyotonia congenita
Parkinson disease type 3
Parkinson disease type 9
Paroxysmal exertion-induced dyskinesia
Paroxysmal extreme pain disorder
Paroxysmal hemicrania
Paroxysmal kinesigenic choreoathetosis
Paroxysomal nonkinesigenic dyskinesia
Parsonage Turner syndrome
Partington syndrome
PCDH19-related female-limited epilepsy
Pediatric autoimmune neuropsychiatric disorders associated with Streptococcus infections
PEHO syndrome
Pelizaeus-Merzbacher disease
Periventricular heterotopia
Periventricular leukomalacia
Perry syndrome
Peters plus syndrome
Pfeiffer Mayer syndrome
Pfeiffer Palm Teller syndrome
Pfeiffer-type cardiocranial syndrome
PGM3-CDG
PHACE syndrome
Phosphoglycerate kinase deficiency
Phosphoglycerate mutase deficiency
Phosphoserine aminotransferase deficiency
Photosensitive epilepsy
Pitt-Hopkins syndrome
Pitt-Hopkins-like syndrome
Plasmacytoma
Pleomorphic xanthoastrocytoma
PMM2-CDG (CDG-Ia)
POEMS syndrome
Poliomyelitis
POLR3-Related Leukodystrophy
Polyarteritis nodosa
Polycystic lipomembranous osteodysplasia with sclerosing leukoencephalopathy
Polyneuropathy-intellectual disability-acromicria-premature menopause syndrome
Pontine tegmental cap dysplasia
Pontocerebellar hypoplasia
Pontocerebellar hypoplasia type 1
Pontocerebellar hypoplasia type 2
Pontocerebellar hypoplasia type 3
Pontocerebellar hypoplasia type 4
Pontocerebellar hypoplasia type 5
Pontocerebellar hypoplasia type 6
Post Polio syndrome
Posterior column ataxia
Posterior column ataxia with retinitis pigmentosa
Postnatal progressive microcephaly, seizures, and brain atrophy
Potassium aggravated myotonia
Potocki-Lupski syndrome
PPM-X syndrome
Prader-Willi habitus, osteopenia, and camptodactyly
Primary amebic meningoencephalitis
Primary angiitis of the central nervous system
Primary basilar impression
Primary carnitine deficiency
Primary central nervous system lymphoma
Primary Familial Brain Calcification
Primary lateral sclerosis
Primary melanoma of the central nervous system
Primary orthostatic tremor
Primary progressive aphasia
Primrose syndrome
Progressive bulbar palsy
Progressive encephalomyelitis with rigidity and myoclonus
Progressive external ophthalmoplegia, autosomal recessive 1
Progressive hemifacial atrophy
Progressive non-fluent aphasia
Prolidase deficiency
Proteus syndrome
Proud syndrome
Pseudoaminopterin syndrome
Pseudocholinesterase deficiency
Pseudoneonatal adrenoleukodystrophy
Pseudoprogeria syndrome
Pseudotrisomy 13 syndrome
Pseudoxanthoma elasticum
Pterygium colli mental retardation digital anomalies
Pudendal Neuralgia
Pure autonomic failure
Pyridoxal 5'-phosphate-dependent epilepsy
Pyridoxine-dependent epilepsy
Pyruvate dehydrogenase phosphatase deficiency
Qazi Markouizos syndrome
Radiation induced brachial plexopathy
Ramos Arroyo Clark syndrome
Rapid-onset dystonia-parkinsonism
Rasmussen encephalitis
Reardon Wilson Cavanagh syndrome
Reducing body myopathy
Refsum disease
Refsum disease, infantile form
Renal dysplasia-limb defects syndrome
Renier Gabreels Jasper syndrome
Restless legs syndrome, susceptibility to, 1 - See
Restless legs syndrome
Restless legs syndrome, susceptibility to, 2 - See
Restless legs syndrome
Restless legs syndrome, susceptibility to, 3 - See
Restless legs syndrome
Restless legs syndrome, susceptibility to, 4 - See
Restless legs syndrome
Restless legs syndrome, susceptibility to, 5 - See
Restless legs syndrome
Restless legs syndrome, susceptibility to, 6 - See
Restless legs syndrome
Retinal arterial macroaneurysm with supravalvular pulmonic stenosis
Retinal vasculopathy with cerebral leukodystrophy with systemic manifestations
Rett syndrome
Reversible cerebral vasoconstriction syndrome
RFT1-CDG (CDG-In)
Rhabdoid tumor
Rhizomelic chondrodysplasia punctata type 1
Riboflavin transporter deficiency
Richards-Rundle syndrome
Richieri Costa Da Silva syndrome
Rigid spine syndrome
Ring chromosome 10
Ring chromosome 14
Ring chromosome 20
Rippling muscle disease
RNAse T2-deficient leukoencephalopathy
Roussy Levy syndrome
RRM2B-related mitochondrial DNA depletion syndrome
Ruvalcaba syndrome
Salla disease - See
Free sialic acid storage disease
Sandhoff disease
Sandifer syndrome
Sarcoidosis - Not a rare disease
Say Barber Miller syndrome
Say Meyer syndrome
Scapuloperoneal syndrome, neurogenic, Kaeser type
SCARF syndrome
Schaaf-Yang syndrome
Scheie syndrome
Schimke immunoosseous dysplasia
Schindler disease type 1
Schinzel Giedion syndrome
Schisis association
Schizencephaly
Schwannomatosis
Schwartz Jampel syndrome
Scott Bryant Graham syndrome
Seaver Cassidy syndrome
Seckel syndrome
Semantic dementia
Sensory ataxic neuropathy, dysarthria, and ophthalmoparesis
Sepiapterin reductase deficiency
Septo-optic dysplasia spectrum
SeSAME syndrome
SETBP1 disorder
Severe congenital nemaline myopathy
Severe intellectual disability-progressive spastic diplegia syndrome
Severe X-linked intellectual disability, Gustavson type
Shapiro syndrome
Short-chain acyl-CoA dehydrogenase deficiency
Shoulder girdle defect mental retardation familial
Shprintzen omphalocele syndrome
Shprintzen-Goldberg craniosynostosis syndrome
Sialidosis type I
Sialidosis, type II
Sickle cell anemia
Simpson-Golabi-Behmel syndrome
Single upper central incisor
Sjogren-Larsson syndrome
SLC35A1-CDG (CDG-IIf)
SLC35A2-CDG
SLC35C1-CDG (CDG-IIc)
Slow-channel congenital myasthenic syndrome
Smith-Fineman-Myers syndrome
Smith-Lemli-Opitz syndrome
Smith-Magenis syndrome
Sneddon syndrome
Snyder-Robinson syndrome
Sonoda syndrome
Spasmodic dysphonia
Spastic ataxia Charlevoix-Saguenay type
Spastic diplegia cerebral palsy
Spastic diplegia infantile type
Spastic paraplegia 1
Spastic paraplegia 10
Spastic paraplegia 11
Spastic paraplegia 12
Spastic paraplegia 13
Spastic paraplegia 14
Spastic paraplegia 15
Spastic paraplegia 16
Spastic paraplegia 17
Spastic paraplegia 18
Spastic paraplegia 19
Spastic paraplegia 2
Spastic paraplegia 23
Spastic paraplegia 24
Spastic paraplegia 25
Spastic paraplegia 26
Spastic paraplegia 29
Spastic paraplegia 3
Spastic paraplegia 31
Spastic paraplegia 32
Spastic paraplegia 39
Spastic paraplegia 4
Spastic paraplegia 51
Spastic paraplegia 5A
Spastic paraplegia 6
Spastic paraplegia 7
Spastic paraplegia 8
Spastic paraplegia 9
Spastic paraplegia facial cutaneous lesions
Spastic paraplegia-epilepsy-intellectual disability syndrome
Spastic paraplegia-glaucoma-intellectual disability syndrome
Spastic tetraplegia-retinitis pigmentosa-intellectual disability syndrome
Spastic tetraplegia-thin corpus callosum-progressive postnatal microcephaly syndrome
Spina bifida occulta - Not a rare disease
Spinal atrophy ophthalmoplegia pyramidal syndrome
Spinal meningioma
Spinal muscular atrophy 1
Spinal muscular atrophy type 2
Spinal muscular atrophy type 3
Spinal muscular atrophy-progressive myoclonic epilepsy syndrome
Spinal shock
Spinocerebellar ataxia
Spinocerebellar ataxia 1
Spinocerebellar ataxia 10
Spinocerebellar ataxia 11
Spinocerebellar ataxia 12
Spinocerebellar ataxia 13
Spinocerebellar ataxia 14
Spinocerebellar ataxia 15
Spinocerebellar ataxia 17
Spinocerebellar ataxia 18
Spinocerebellar ataxia 19 and 22
Spinocerebellar ataxia 2
Spinocerebellar ataxia 20
Spinocerebellar ataxia 21
Spinocerebellar ataxia 23
Spinocerebellar ataxia 25
Spinocerebellar ataxia 26
Spinocerebellar ataxia 27
Spinocerebellar ataxia 28
Spinocerebellar ataxia 29
Spinocerebellar ataxia 3
Spinocerebellar ataxia 30
Spinocerebellar ataxia 31
Spinocerebellar ataxia 34
Spinocerebellar ataxia 4
Spinocerebellar ataxia 5
Spinocerebellar ataxia 7
Spinocerebellar ataxia 8
Spinocerebellar ataxia 9
Spinocerebellar ataxia autosomal recessive 3
Spinocerebellar ataxia autosomal recessive 4
Spinocerebellar ataxia autosomal recessive 5
Spinocerebellar ataxia autosomal recessive 6
Spinocerebellar ataxia autosomal recessive 7
Spinocerebellar ataxia autosomal recessive 8
Spinocerebellar ataxia autosomal recessive with axonal neuropathy
Spinocerebellar ataxia type 6
Spinocerebellar ataxia with dysmorphism
Spinocerebellar ataxia X-linked type 2
Spinocerebellar ataxia X-linked type 3
Spinocerebellar ataxia X-linked type 4
Spinocerebellar degeneration and corneal dystrophy
Split hand urinary anomalies spina bifida
Split spinal cord malformation
Spondyloepiphyseal dysplasia congenita
SRD5A3-CDG (CDG-Iq)
SSR4-CDG
STAC3 Disorder
Status epilepticus
Steinfeld syndrome
Stiff person syndrome
Stocco dos Santos syndrome
Striatonigral degeneration infantile
Sturge-Weber syndrome
Subacute sclerosing panencephalitis
Subcortical band heterotopia
Subependymal giant cell astrocytoma
Subependymoma
Succinic semialdehyde dehydrogenase deficiency
Susac syndrome
Symmetrical thalamic calcifications
Tangier disease
TANGO2-Related Metabolic Encephalopathy and Arrhythmias
Tarlov cysts
Tay-Sachs disease
Tel Hashomer camptodactyly syndrome
Telfer Sugar Jaeger syndrome
Temple syndrome
Temple-Baraitser syndrome
Temporal epilepsy, familial
Temtamy syndrome
Tethered cord syndrome
Thoracic dysplasia hydrocephalus syndrome
Thoracic outlet syndromes - Not a rare disease
Thyrotoxic periodic paralysis
TMEM165-CDG (CDG-IIk)
Toriello-Carey syndrome
Tourette syndrome - Not a rare disease
Tranebjaerg Svejgaard syndrome
Transverse myelitis
Trichinosis
Trichorhinophalangeal syndrome type 2
Trigeminal neuralgia
Triosephosphate isomerase deficiency
Triple A syndrome
Troyer syndrome
Tuberous sclerosis complex
Tubular aggregate myopathy
Tumefactive multiple sclerosis
Typical congenital nemaline myopathy
Tyrosine hydroxylase deficiency
Tyrosinemia type 1
Ullrich congenital muscular dystrophy
Unverricht-Lundborg disease
Van Benthem-Driessen-Hanveld syndrome
Van Den Bosch syndrome
Variant Creutzfeldt-Jakob disease
Variegate porphyria
Vein of Galen aneurysm
Vici syndrome
Viljoen Kallis Voges syndrome
Visual snow syndrome
VLCAD deficiency
Vogt-Koyanagi-Harada disease
Von Hippel-Lindau disease
Walker-Warburg syndrome
Weaver syndrome
Welander distal myopathy, Swedish type
Wernicke-Korsakoff syndrome
West syndrome
Whipple disease
White matter hypoplasia-corpus callosum agenesis-intellectual disability syndrome
Wiedemann Oldigs Oppermann syndrome
Williams syndrome
Wilson disease
Wilson-Turner syndrome
Wolf-Hirschhorn syndrome
Wolman disease
Woodhouse Sakati syndrome
Worster Drought syndrome
Wrinkly skin syndrome
Wyburn-Mason syndrome
X-linked cerebral adrenoleukodystrophy
X-linked Charcot-Marie-Tooth disease type 1 - See
Charcot-Marie-Tooth disease
X-linked Charcot-Marie-Tooth disease type 2 - See
Charcot-Marie-Tooth disease
X-linked Charcot-Marie-Tooth disease type 3 - See
Charcot-Marie-Tooth disease
X-linked Charcot-Marie-Tooth disease type 4 - See
Charcot-Marie-Tooth disease
X-linked Charcot-Marie-Tooth disease type 5 - See
Charcot-Marie-Tooth disease
X-linked Charcot-Marie-Tooth disease type 6 - See
Charcot-Marie-Tooth disease
X-linked complicated corpus callosum agenesis - See
L1 syndrome
X-linked complicated spastic paraplegia type 1 - See
L1 syndrome
X-linked creatine deficiency
X-linked dystonia-parkinsonism/Lubag
X-linked hereditary sensory and autonomic neuropathy with deafness
X-linked intellectual disability - corpus callosum agenesis - spastic quadriparesis
X-linked intellectual disability - short stature – obesity
X-linked intellectual disability, Najm type
X-linked intellectual disability, Schimke type
X-linked intellectual disability, Siderius type
X-linked intellectual disability, Turner type
X-linked intellectual disability-dysmorphism-cerebral atrophy syndrome
X-linked intellectual disability-plagiocephaly syndrome
X-linked lissencephaly with abnormal genitalia
X-linked myopathy with excessive autophagy
X-linked myotubular myopathy
X-linked non-specific intellectual disability
X-linked periventricular heterotopia
Xeroderma pigmentosum
Xia-Gibbs syndrome
XK aprosencephaly
Zechi Ceide syndrome
Zellweger syndrome
ZTTK syndrome