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Abnormal CNS myelination

MedGen UID:
Concept ID:
Anatomical Abnormality
Synonym: Abnormal formation of myelin sheaths
HPO: HP:0011400


An abnormality of myelination of nerves in the central nervous system. [from HPO]

Term Hierarchy

CClinical test,  RResearch test,  OOMIM,  GGeneReviews,  VClinVar  
  • Abnormal CNS myelination

Conditions with this feature

Glycogen storage disease, type II
MedGen UID:
Concept ID:
Disease or Syndrome
Pompe disease is classified by age of onset, organ involvement, severity, and rate of progression. Infantile-onset Pompe disease (IOPD; individuals with onset before age 12 months with cardiomyopathy) may be apparent in utero but more typically onset is at the median age of four months with hypotonia, generalized muscle weakness, feeding difficulties, failure to thrive, respiratory distress, and hypertrophic cardiomyopathy. Without treatment by enzyme replacement therapy (ERT), IOPD commonly results in death by age two years from progressive left ventricular outflow obstruction and respiratory insufficiency. Late-onset Pompe disease (LOPD; including: (a) individuals with onset before age 12 months without cardiomyopathy; and (b) all individuals with onset after age 12 months) is characterized by proximal muscle weakness and respiratory insufficiency; clinically significant cardiac involvement is uncommon.
Hurler syndrome
MedGen UID:
Concept ID:
Disease or Syndrome
Mucopolysaccharidosis type I (MPS I) is a progressive multisystem disorder with features ranging over a continuum of severity. While affected individuals have traditionally been classified as having one of three MPS I syndromes (Hurler syndrome, Hurler-Scheie syndrome, or Scheie syndrome), no easily measurable biochemical differences have been identified and the clinical findings overlap. Affected individuals are best described as having either a phenotype consistent with either severe (Hurler syndrome) or attenuated MPS I, a distinction that influences therapeutic options. Severe MPS I. Infants appear normal at birth. Typical early manifestations are nonspecific (e.g., umbilical or inguinal hernia, frequent upper respiratory tract infections before age 1 year). Coarsening of the facial features may not become apparent until after age one year. Gibbus deformity of the lower spine is common and often noted within the first year. Progressive skeletal dysplasia (dysostosis multiplex) involving all bones is universal, as is progressive arthropathy involving most joints. By age three years, linear growth decreases. Intellectual disability is progressive and profound but may not be readily apparent in the first year of life. Progressive cardiorespiratory involvement, hearing loss, and corneal clouding are common. Without treatment, death (typically from cardiorespiratory failure) usually occurs within the first ten years of life. Attenuated MPS I. Clinical onset is usually between ages three and ten years. The severity and rate of disease progression range from serious life-threatening complications leading to death in the second to third decade, to a normal life span complicated by significant disability from progressive joint manifestations and cardiorespiratory disease. While some individuals have no neurologic involvement and psychomotor development may be normal in early childhood, learning disabilities and psychiatric manifestations can be present later in life. Hearing loss, cardiac valvular disease, respiratory involvement, and corneal clouding are common.
Pelizaeus-Merzbacher disease
MedGen UID:
Concept ID:
Disease or Syndrome
PLP1 disorders of central nervous system myelin formation include a range of phenotypes from Pelizaeus-Merzbacher disease (PMD) to spastic paraplegia 2 (SPG2). PMD typically manifests in infancy or early childhood with nystagmus, hypotonia, and cognitive impairment; the findings progress to severe spasticity and ataxia. Life span is shortened. SPG2 manifests as spastic paraparesis with or without CNS involvement and usually normal life span. Intrafamilial variation of phenotypes can be observed, but the signs are usually fairly consistent within families. Heterozygous females may manifest mild-to-moderate signs of the disease.
Xeroderma pigmentosum group B
MedGen UID:
Concept ID:
Disease or Syndrome
Xeroderma pigmentosum (XP) is characterized by: Acute sun sensitivity (severe sunburn with blistering, persistent erythema on minimal sun exposure) with marked freckle-like pigmentation of the face before age two years; Sunlight-induced ocular involvement (photophobia, severe keratitis, atrophy of the skin of the lids, ocular surface neoplasms); Greatly increased risk of sunlight-induced cutaneous neoplasms (basal cell carcinoma, squamous cell carcinoma, melanoma) within the first decade of life. Approximately 25% of affected individuals have neurologic manifestations (acquired microcephaly, diminished or absent deep tendon stretch reflexes, progressive sensorineural hearing loss, progressive cognitive impairment, and ataxia). The most common causes of death are skin cancer, neurologic degeneration, and internal cancer. The median age at death in persons with XP with neurodegeneration (29 years) was found to be younger than that in persons with XP without neurodegeneration (37 years).
Renal tubular acidosis, distal, with nephrocalcinosis, short stature, intellectual disability, and distinctive facies
MedGen UID:
Concept ID:
Disease or Syndrome
Cystic leukoencephalopathy without megalencephaly
MedGen UID:
Concept ID:
Disease or Syndrome
RNAse T2-deficient leukoencephalopathy is a disorder that affects the brain. People with RNAse T2-deficient leukoencephalopathy have neurological problems that become apparent during infancy; the problems generally do not worsen over time (progress). Most affected individuals have severe intellectual disability; muscle stiffness (spasticity); and a delay in developing motor skills such as sitting, crawling, and walking. Some do not learn to walk, and most do not develop the ability to speak. Other neurological features that can occur in RNAse T2-deficient leukoencephalopathy include hearing loss caused by abnormalities in the inner ear (sensorineural deafness), seizures, involuntary writhing movements of the hands (athetosis), uncontrolled muscle tensing (dystonia), and involuntary eye movements (nystagmus). In addition to the neurological problems associated with this disorder, some affected individuals have unusual facial features sometimes described as a "doll-like face."\n\nThe neurological problems in this disorder are caused by abnormalities in the brain. People with this condition have leukoencephalopathy, an abnormality of the brain's white matter that can be detected with medical imaging. White matter consists of nerve fibers covered by a fatty substance called myelin. Myelin insulates nerve fibers and promotes the rapid transmission of nerve impulses. In people with RNAse T2-deficient leukoencephalopathy, myelin is not made in sufficient amounts during development, leading to patchy white matter abnormalities (lesions) in the brain. In addition, individuals with RNAse T2-deficient leukoencephalopathy may have cysts in regions of the brain called the temporal lobes and enlargement of the fluid-filled cavities (ventricles) near the center of the brain. The white matter lesions are primarily concentrated around the cysts and the ventricles. An abnormally small head and brain size (microcephaly) often occurs in this disorder.
Immunodeficiency 23
MedGen UID:
Concept ID:
Disease or Syndrome
IMD23 is an autosomal recessive primary immunodeficiency syndrome characterized by onset of recurrent infections, usually respiratory or cutaneous, in early childhood. Immune workup usually shows neutropenia, lymphopenia, eosinophilia, and increased serum IgE or IgA. Neutrophil chemotactic defects have also been reported. Infectious agents include bacteria, viruses, and fungi. Many patients develop atopic dermatitis, eczema, and other signs of autoinflammation. Affected individuals may also show developmental delay or cognitive impairment of varying severity (summary by Bjorksten and Lundmark, 1976 and Zhang et al., 2014).
Mitochondrial complex 4 deficiency, nuclear type 10
MedGen UID:
Concept ID:
Disease or Syndrome
Mitochondrial complex IV deficiency nuclear type 10 (MC4DN10) is an autosomal recessive multisystem metabolic disorder characterized by the onset of severe symptoms soon after birth. Affected infants have respiratory and neurologic distress, metabolic lactic acidosis, and dysmorphic features, including microphthalmia. Death occurs in early infancy. Postmortem examination has demonstrated systemic involvement with hepatomegaly, hypertrophic cardiomyopathy, renal hypoplasia, and adrenal hyperplasia. There is also abnormal brain myelination and cavitating brain lesions. Patient tissues show decreased levels and activity of mitochondrial respiratory complex IV (summary by Weraarpachai et al., 2012). For a discussion of genetic heterogeneity of mitochondrial complex IV (cytochrome c oxidase) deficiency, see 220110.
Hengel-Maroofian-Schols syndrome
MedGen UID:
Concept ID:
Disease or Syndrome
Hengel-Maroofian-Schols syndrome (HEMARS) is an autosomal recessive neurodevelopmental disorder characterized by severe global developmental delay apparent from infancy or early childhood. Affected individuals have delayed walking or inability to walk, impaired intellectual development with poor or absent speech, pyramidal signs manifest as lower limb spasticity, poor overall growth often with short stature and microcephaly, and dysmorphic facial features. Some patients develop seizures. Brain imaging shows thinning of the posterior part of the corpus callosum, delayed myelination, and cerebral and cerebellar atrophy (Hengel et al., 2021).

Professional guidelines


Tobin WO, Guo Y, Krecke KN, Parisi JE, Lucchinetti CF, Pittock SJ, Mandrekar J, Dubey D, Debruyne J, Keegan BM
Brain 2017 Sep 1;140(9):2415-2425. doi: 10.1093/brain/awx200. PMID: 29050399
Steen VM, Skrede S, Polushina T, López M, Andreassen OA, Fernø J, Hellard SL
Eur Neuropsychopharmacol 2017 Jun;27(6):589-598. Epub 2016 Aug 1 doi: 10.1016/j.euroneuro.2016.07.011. PMID: 27492885
KhorshidAhmad T, Acosta C, Cortes C, Lakowski TM, Gangadaran S, Namaka M
Mol Neurobiol 2016 Mar;53(2):1092-1107. Epub 2015 Jan 13 doi: 10.1007/s12035-014-9074-1. PMID: 25579386

Recent clinical studies


Cömert C, Brick L, Ang D, Palmfeldt J, Meaney BF, Kozenko M, Georgopoulos C, Fernandez-Guerra P, Bross P
Cold Spring Harb Mol Case Stud 2020 Jun;6(3) Epub 2020 Jun 12 doi: 10.1101/mcs.a004879. PMID: 32532876Free PMC Article


Muirhead KJ, Clause AR, Schlachetzki Z, Dubbs H, Perry DL, Hagelstrom RT, Taft RJ, Vanderver A
Cold Spring Harb Mol Case Stud 2021 Dec;7(6) Epub 2021 Dec 9 doi: 10.1101/mcs.a006143. PMID: 34737199Free PMC Article
Cömert C, Brick L, Ang D, Palmfeldt J, Meaney BF, Kozenko M, Georgopoulos C, Fernandez-Guerra P, Bross P
Cold Spring Harb Mol Case Stud 2020 Jun;6(3) Epub 2020 Jun 12 doi: 10.1101/mcs.a004879. PMID: 32532876Free PMC Article

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