Foo et al [39] probed 39 genes implicated in PD by GWAS and described enrichment of rare missense variation in LRRK2. Sandor et al [40] investigated 329 genes located within GWAS loci, and detected a possible enrichment of missense variation, including both common and rare mutations in their analysis, across the complete gene set. Here, LRRK2 is linked to Parkinson disease.