Table 3.

Evidence of purifying selection at the LRRK2 locus

	NS variants	S variants	NS:S	OR 95% CI	P-value
Singletons	140	64	2.2	-	-
No singletons	68	46	1.5	0.68 (0.41-1.12)	0.11
No singletons or doubletons	47	28	1.7	0.77 (0.43-1.40)	0.39
MAF > 0.1%	11	10	1.1	0.50 (0.18-1.40)	0.15
MAF > 0.5%	9	8	1.1	0.51 (0.17-1.61)	0.19
MAF > 5%	5	8	0.6	0.29 (0.07-1.04)	0.03

Numbers of non-synonymous (NS) and synonymous (S) variants in 12,514 white Europeans are indicated for the entire LRRK2 gene. Ratio of NS to S variants (NS:S) were calculated for different variant frequency categories because purifying selection increases with variant frequency for functionally damaging NS variants (Kryukov et al. 2007). The “Singletons” variant category is the subset of NS and S variants observed once in 12,514 white Europeans. The “No singletons” variant category is the subset of all NS and S variants that are not singletons, and the “No singletons or doubletons” category is the subset of all variants observed more than twice. Association tests were conducted for NS:S by testing variant counts in two-by-two contingency tables for each frequency category compared to “Singletons”. MAF = minor allele frequency.