Other Names for this Disease
- Ataxia, chorea, seizures, and dementia
- Dentatorubropallidoluysian atrophy
- Haw River syndrome
- Myoclonic epilepsy with choreoathetosis
DRPLA is inherited in an autosomal dominant pattern, which means that one copy of the mutated gene in each cell is sufficient to cause the disorder. The condition may be inherited from an affected parent or may occur for the first time in the affected individual. In most cases, an affected person has one parent with the condition.
The CAG trinucleotide repeat in the ATN1 gene often increases in size (resulting in a greater number of repeats) when the mutated gene is transmitted from a parent to a child. This "instability" during transmission of the gene results in a phenomenon called anticipation. This means that larger repeat expansions in subsequent generations are usually associated with an earlier onset of the condition and more severe signs and symptoms. Anticipation seen in DRPLA tends to be more prominent when the ATN1 gene is inherited from a person's father (paternal inheritance) than when it is inherited from a person's mother (maternal inheritance). Affected offspring typically have symptoms 26 to 29 years earlier than affected fathers and 14 to 15 years earlier than affected mothers.
- Dentatorubral-pallidoluysian atrophy. Genetics Home Reference (GHR). 2008; http://ghr.nlm.nih.gov/condition=dentatorubralpallidoluysianatrophy. Accessed 5/10/2010.
- Shoji Tsuji. DRPLA. GeneReviews. June 1, 2010; http://www.ncbi.nlm.nih.gov/books/NBK1491/. Accessed 9/5/2012.