Identification of expanded and interrupted ATXN2 repeat expansions in Parkinson’s disease and Lewy Body Dementia cohorts.

Researchers conducted a study to see whether repeat expansions in the genetic code—similar to those seen in Huntington’s disease—were also present in the ATXN2 gene in people with Parkinson’s disease and Lewy Body Dementia. ATXN2 repeat expansions are abnormal increases in CAG (the three-letter DNA sequence) trinucleotide repeats in the ATXN2 gene.

Previous research has shown that ATXN2 expansions are linked to spinocerebellar ataxia type 2 (SCA2) and amyotrophic lateral sclerosis (ALS), and may also play a role in Parkinsonism and multisystem atrophy (MSA).

In this study, researchers analyzed whole-genome sequencing data from 7,835 people to identify ATXN2 repeat expansions. Their findings concluded that ATXN2 expansions were found in 4 out of 2,431 Parkinson’s patients and 2 out of 2,468 Lewy body Dementia patients, suggesting that these expansions may help to contribute to the risk of someone getting these diseases, but the numbers (at least from this test) are small.