On May 29, 2024, 23andMe with support from The Michael J. Fox Foundation for Parkinson’s Research, announced it had conducted the world’s largest study on LRRK2 G2019S and uncovered new insights into the variant.

Parkinson’s disease is associated with the degeneration of nerves in the brain and body, which produces different symptoms according to the pattern of nerve death. Only 10 percent of Parkinson’s disease cases have a known genetic cause; the remaining 90 percent have idiopathic Parkinson’s disease, where the cause is unknown.

23andMe launched the Parkinson’s Impact Project (PIP) in 2018 to better understand which LRRK2 G2019S carriers’ are at greatest risk of developing Parkinson’s disease. The 3.5-year longitudinal study included 1,286 genotyped LRRK2 G2019S carriers and 109,154 non-carriers. Findings from the study, published in Brain, illustrated how DNA weaves together health, ancestry, and history.