Figure 2
From: Circadian Clock Model Supports Molecular Link Between PER3 and Human Anxiety
Associations of the PER3 length polymorphism (VNTR) with circadian chronotype and anxiety. (A) Frequencies of 4- and 5-repeat alleles in morning-type (n = 46), intermediates (n = 136), and evening-type (n = 62) self-reported chronotypes. The frequency of the PER3 4 allele is higher in evening-types and lower in morning-types (OR = 0.52 95% CI = 0.280–0.975, p = 0.042). (B) Frequencies of the PER3 VNTR genotypes in each chronotype. Per3 4,4 homozygotes are less frequent in morning-types (χ2 = 5.71, df = 1, p = 0.017) and PER3 5,5 homozygotes are less frequent in evening-types (χ2 = 40.90, df = 1, p < 0.001). C)Average self-reported MEQ scores (±SD) are lower for PER3 4,4 homozygotes than for PER3 4,5 or PER3 5,5 types (F(2, 242) = 9.98, p < 0.001). D) Average trait anxiety scores (±SD) are higher in individuals carrying a PER3 4 allele (t = 2.12, df = 242, p = 0.035).
