Infantile Refsum disease is a rare, inherited disorder of peroxisome formation. Peroxisomes are tiny structures inside cells that process fats and detoxify ...

Neonatal adrenoleukodystrophy (NALD) is a rare genetic disorder in newborns caused by a failure in the normal formation and function of peroxisomes—tiny ...

Zellweger syndrome (ZS) is a rare, inherited disorder that affects the body’s ability to build and maintain peroxisomes—tiny structures within cells that break ...

X-linked complicated corpus callosum dysgenesis is a rare genetic condition that affects the way the corpus callosum—the wide band of nerve fibers connecting ...

X-linked Charcot–Marie–Tooth disease (often abbreviated CMTX) is a hereditary peripheral neuropathy that affects the insulating sheath (myelin) and the long ...

Williams syndrome (WS), also known as Williams–Beuren syndrome, is a rare genetic disorder caused by a microdeletion of about 25–27 genes on the long arm of ...

Wernicke–Korsakoff syndrome is a serious brain disorder caused by a lack of thiamine (vitamin B1), which the body needs to convert sugar into energy for normal ...

Adult progeria, formally known as Werner syndrome (WS), is a rare genetic disorder that causes the body’s cells to age much faster than normal. People with WS ...

Werner syndrome is a rare autosomal recessive genetic disorder marked by the early onset of features normally seen in later life. People with Werner syndrome ...

Superior alternating hemiplegia, commonly known as Weber’s syndrome, is a rare brainstem stroke syndrome resulting from a lesion in the ventral midbrain. It is ...

Weber’s syndrome, also known as superior alternating hemiplegia or midbrain stroke syndrome, is a neurological condition caused by damage to the ventral ...

Walker–Warburg syndrome (WWS) is a rare, autosomal recessive congenital muscular dystrophy distinguished by severe abnormalities of the muscles, brain, and ...

TRPM3-related neurodevelopmental disorder (TRPM3-NDD) is a rare monogenic condition caused by pathogenic variants in the TRPM3 gene. This disorder primarily ...

Triploid syndrome, also called triploidy, is a rare chromosomal disorder in which every cell of the body has three complete sets of chromosomes (69 total) ...

SYNGAP1-related intellectual disability (SYNGAP1-ID) is a rare, monogenic neurodevelopmental disorder caused by loss-of-function changes in the SYNGAP1 ...

Susac’s syndrome is a rare autoimmune disease characterized by an immune-mediated endotheliopathy affecting the smallest blood vessels in the brain, retina, ...

Subclavian steal syndrome (SSS), also known as subclavian-vertebral artery steal syndrome or subclavian steal steno-occlusive disease, is a vascular condition ...

Sturge–Weber syndrome (SWS) is a rare congenital neurocutaneous disorder characterized by facial capillary malformations (“port-wine stains”), leptomeningeal ...

Stiff-person syndrome (SPS) is a rare, progressive neurological disorder characterized by muscle stiffness and painful spasms that primarily affect the trunk ...

Cerebral gigantism, historically known as “cerebral gigantism in childhood” and now most often referred to as Sotos syndrome, is a rare genetic overgrowth ...