Abovementioned symptoms
Hereditary Motor and Sensory Neuropathy with Cataract - HYCCIN
Clinical Features
Patients with hypomyelinating leucodystrophy with congenital cataract (HCC) reveal congenital cataract, progredient neurological impairment as wellas a diffuse lack of myelin (visible in MRT). A psychomotoric retardation begins at the end of the first year of life. Walking is only possible with support. Pyramidal and cerebellar dysfunction increases, sometimes with dysarthry and intention tremor. Muscle weakness and atrophy frequently occur in the lower extremities. Mental retardation is mildly to medium. Cortex and grey matter remain unaffected, but a diffuse cerebral hypomyelinisation occurs. Neurophysiologically, a peripheral neuropathy is observed in almost all cases. Sural nerve biopsy also reveals signs of a hypomyelination and a mild axonal loss (depending on the stage of development).
Genetic Information
HCC is an autosomal recessive inheritance. The HYCCIN gene is located on chromosome 7p15.3. Other names for this gene are Downregulated by CTNNB1, protein A (DRCTNNB1A) and Family with sequence similarity 126, member A (FAM126A).
Prevalence
Rare
Diagnostic
Indication
Method
Mutation analysis of all coding regions, flanking intronic regions, as well as the 5´ and 3´ untranslated regions of the HYCCIN gene by means of DNA sequencing.
Sample Requirement
2 - 4 ml of EDTA blood
Duration
4 - 6 weeks