Table 2. Susceptibility Genes/Loci for Parkinson Disease.

PARK Locus	Gene	Map Position	Risk variants	Approximate Odds Ratio for PD
Well-validated loci/genes
PARK1/PARK4	SNCA	4q21	REP1 repeat polymorphism, multiple SNPs in 3′ half of gene	1.2-1.4
PARK8	LRRK2	12q12	G2385R, R1628P	2.0-2.2
Not assigned	MAPT	17q21.1	H1 haplotype	1.4
Not assigned	GBA	1q21	>300 mutations including; N370S and L444P	5.4
Putative loci/genes
PARK16	Unknown	1q32	Multiple SNPs from GWASs	1.3-1.4
PARK17	GAK	4p16	Multiple SNPs from GWASs	1.5
PARK18	HLA-DRA	6p21.3	Multiple SNPs from GWASs	1.3

Abbreviations: GWASs, genomewide association studies; PD, Parkinson disease; SNP, single nucleotide polymorphism.

Adapted from PDGene Web site (http://www.pdgene.org) and references 18, ²⁷, and ²⁸.