In addition, genome-wide association studies (GWAS) of very large collectives of late-manifesting sporadic PD cases identified two regions on chromosome 4 (SNCA locus and CPLX1/GAK/TMEM175/DGKQ locus) that contain genetic variants predisposing to multifactorial PD (Lill et al., 2012; Nalls et al., 2014). Here, CPLX1 is linked to Parkinson disease.