Huntington’s Disease-Like 2
Huntington’s disease-like 2 (HDL2) is an autosomal dominant disease caused by a trinucleotide CTG/CAG repeat expansion in the gene for junctophilin-3 located on chromosome 16q24.3. It was initially described in a large African-American family in the southeastern United States. Subsequent studies have shown it to be a very rare cause of the Huntington’s disease (HD) phenotype which occurs almost exclusively in individuals of African descent. Clinically, HDL2 closely resembles HD and causes chorea, dystonia, dysarthria, disturbed gait and balance, psychiatric symptoms, dementia, and weight loss. Onset is usually in the fourth decade with gradual progression to death within 20 years.
KeywordsInvoluntary Movement Repeat Expansion Autosomal Dominant Disease Cortical Atrophy African Descent
Huntington’s disease-like 2.mp4 (MP4 13,080KB)
The patient displays nearly continuous choreiform movements of her hands, fingers, and ankles, milder head movements, reduced facial expression, and impersistence of tongue protrusion.