Clinical features
Individuals with DEGS1-related leukodystrophy present a global developmental delay or developmental regression at 6-18 months, leading to mild to severe intellectual disability. They have limb rigidity, epilepsy, abnormal ocular movements and profound failure to thrive.
MRI show a reduced ability to form myelin (hypomyelination), thinning of the corpus callosum and progressive thalamic and cerebellar atrophy.
Prevalence
The prevalence of DEGS1-related leukodystrophy cannot be ascertained because of the limited number of cases identified to date.
Inheritance
DEGS1-related leukodystrophy is a genetic disorder due to mutations in DEGS1. The disease is inherited in an autosomal recessive manner: this means that both copies of the DEGS1 gene must be mutated in an individual to be affected, whereas heterozygotes (with only one mutated copy) are asymptomatic carriers and thus do not manifest the condition but are at risk of transmitting it. Parents of a patient are usually carriers of the mutations and they have a 25% chance to have other children affected. Therefore, a genetic counselling and testing at risk family members are crucial for these families.