SLC35A2-congenital disorder of glycosylation- MedGen UID:
- 813018
- •Concept ID:
- C3806688
- •
- Disease or Syndrome
Congenital disorder of glycosylation type IIm, or developmental and epileptic encephalopathy-22 (DEE22), is an X-linked dominant severe neurologic disorder characterized by infantile-onset seizures, hypsarrhythmia on EEG, hypotonia, and developmental delay associated with severe intellectual disability and lack of speech. These features are consistent with developmental and epileptic encephalopathy (DEE). Brain malformations usually include cerebral and cerebellar atrophy. Additionally, some patients may have dysmorphic features or coarse facies (Ng et al., 2013; Kodera et al., 2013).
For a general discussion of CDGs, see CDG1A (212065) and CDG2A (212066). For a general phenotypic description and a discussion of genetic heterogeneity of DEE, see 308350.
Classic dopamine transporter deficiency syndrome- MedGen UID:
- 1814585
- •Concept ID:
- C5700336
- •
- Disease or Syndrome
SLC6A3-related dopamine transporter deficiency syndrome (DTDS) is a complex movement disorder with a continuum that ranges from classic early-onset DTDS (in the first 6 months) to atypical later-onset DTDS (in childhood, adolescence, or adulthood). Classic DTDS. Infants typically manifest nonspecific findings (irritability, feeding difficulties, axial hypotonia, and/or delayed motor development) followed by a hyperkinetic movement disorder (with features of chorea, dystonia, ballismus, orolingual dyskinesia). Over time, affected individuals develop parkinsonism-dystonia characterized by bradykinesia (progressing to akinesia), dystonic posturing, distal tremor, rigidity, and reduced facial expression. Limitation of voluntary movements leads to severe motor delay. Episodic status dystonicus, exacerbations of dystonia, and secondary orthopedic, gastrointestinal, and respiratory complications are common. Many affected individuals appear to show relative preservation of intellect with good cognitive development. Atypical DTDS. Normal psychomotor development in infancy and early childhood is followed by later-onset manifestations of parkinsonism-dystonia with tremor, progressive bradykinesia, variable tone, and dystonic posturing. The long-term outcome of this form is currently unknown.