GBA N370S — Parkinson's risk and Gaucher disease carrier status
One copy of the GBA N370S variant — carrier status for Gaucher disease and an increased Parkinson's risk.
You have one copy of a GBA DNA change — you're a carrier for Gaucher disease and have a higher chance of Parkinson's.
Carriers of one GBA N370S variant are typically asymptomatic for Gaucher disease, but have a several-fold increased lifetime risk of Parkinson's disease compared with non-carriers.
With one copy you don't get Gaucher disease itself, but your lifetime chance of Parkinson's disease is several times higher than average.
What this means
GBA encodes glucocerebrosidase, the enzyme deficient in Gaucher disease. Two damaged copies cause Gaucher. One copy was long thought to be benign, but is now recognised as one of the strongest common genetic risk factors for Parkinson's disease and Lewy body dementia, with carriers showing a roughly five-fold increased Parkinson's risk.
GBA makes an enzyme called glucocerebrosidase, which helps break down certain fats inside your cells. Two damaged copies cause Gaucher disease — a condition where those fats build up and cause problems. One copy was long assumed to be harmless. We now know that's not quite right: a single copy is one of the strongest common genetic risk factors for Parkinson's disease and a related condition called Lewy body dementia. People with one copy have roughly five times the average chance of developing Parkinson's over their lifetime.
Caveats
- The Parkinson's effect is a risk modifier, not a guarantee — most carriers never develop Parkinson's.
- Two-copy results may indicate previously undiagnosed Gaucher disease type 1, which is highly treatable; please consult a clinical geneticist.
- Carrier screening implications matter for family planning in populations where the variant is common.
Populations
- Particularly common among Ashkenazi Jewish individuals