Study of a Functional Polymorphism in the PER3 Gene and Diurnal Preference in a Colombian Sample

PER3-VNTR		Diurnal Somnolence		p value	Epworth Sleep Scale Scores Mean (SE)	p value
PER3-VNTR		Normal n (%)	High n (%)	p value	Epworth Sleep Scale Scores Mean (SE)	p value
Genotypes	4/4	148 (64.6)	44 (67.7)	0.15b	10.94 (0.32)	0.32a
	4/5	69 (30.1)	19 (29.2)		11.02 (0.42)
	5/5	12 (5.2)	2 (3.1)		9.43 (1.05)
	Total	229 (100)	65 (100)		10.89 (0.25)
Alleles	4	0.80	0.82	0.13c
Alleles	5	0.22	0.18	0.13c

a. p value derived from a linear regression model (codominant model) b. p value for differences in genotype frequencies between categories (trend model) c. p value for differences in allele frequencies between categories