Elucidating the risk of Parkinson's disease High expression of the α-synuclein gene ( SNCA ) is a risk factor for Parkinson's disease (PD), but certain drugs may mitigate this risk. Mittal et al. ran a small-molecule screen to identify compounds that regulate levels of SNCA expression and found that several β2-adrenoreceptor (β2AR) agonists reduced them (see the Perspective by Snyder). These compounds modulated epigenetic marks at the SNCA gene, effectively suppressing SNCA transcription. The authors looked at the pharmaceutical history of more than 4 million Norwegians over an 11-year period and found a reduced risk of PD among those that were taking one of the β2AR agonists for other medical problems. Science , this issue p. 891 ; see also p. 869