A Novel Study and Meta-Analysis of the Genetic Variation of the Serotonin Transporter Promoter in the Italian Population Do Not Support a Large Effect on Alzheimer's Disease Risk

Table 3

5-HTTLPR and rs25531 genotypic and allelic frequencies.

	Genotype count (%)			Allele count (%)		OR (95% CI) and P value for allelic distribution (L-allele versus S-allele)
	S/S	S/L	L/L	S	L
5-HTTLPR
AD (220)	51 (23.2)	107 (48.6)	62 (28.2)	209 (47.5)	231 (52.5)
CNTR (197)	37 (18.8)	84 (42.6)	76 (38.6)*	158 (40.1)	236 (59.9)	0.74 (0.56–0.97) and 0.03
	Genotype count (%)			Allele count (%)		OR (95% CI) and P value for allelic distribution (G-allele versus A-allele)
	G/G	G/A	A/A	G	A
rs25531
AD (220)	0 (0.0)	31 (13.9)	189 (86.1)	31 (7.0)	409 (93.0)
CNTR (197)	5 (2.5)	26 (13.2)	166 (84.3)^#	36 (9.1)	358 (90.9)	0.75 (0.45–1.24) and 0.29

AD: sporadic Alzheimer’s disease;
CNTR: controls;
*= 0.07; # = 0.06*, P-value calculated from χ ² test for AD versus CNTR as for genotypic distribution;
OR (95% CI): odds ratio and 95% confidence interval calculated from 2×2 contingency table.