Gene-environment interaction between body mass index and transforming growth factor beta 1 (TGFβ1) gene in knee and hip osteoarthritis

Table 4 Significant results from gene-environment interactions of TGFβ1 SNPs and BMI in OA

TGFβ1SNP	OA phenotyp	Interaction	Univariate			Adjusted‡ OR
			ORINT	(95% CI)	P-Value (LRT)	ORINT	(95% CI)	P-Value (LRT)
rs11466321	Knee OA	Multiplicative	0.96	(0.49, 1.91)	0.911	1.08	(0.50, 2.31)	0.851
		RERI	4.25	(2.46, 6.05)		0.67	(-0.92, 2.26)
		AP	0.75	(0.59, 0.90)		0.14	(-0.16, 0.44)
		Synergy Index	10.46	(1.42, 77.30)		1.21	(0.77, 1.89)
rs2278422§	Knee OA	Multiplicative	0.47	(0.27, 0.81)	0.005	0.47	(0.26, 0.86)	0.013
		RERI	-3.09	(-5.37, -0.81)		-2.66	(-4.96, -0.36)
		AP	-0.61	(-0.95, -0.27)		-0.56	(-0.94, -0.17)
		Synergy Index	0.57	(0.45, 0.72)		0.59	(0.44, 0.78)
rs1800468¶	Hip OA	Multiplicative	2.78	(1.46, 5.30)	0.001	2.27	(1.15, 4.48)	0.015
		RERI	1.06	(0.38, 1.75)		0.93	(0.19, 1.67)
		AP	0.46	(0.24, 0.68)		0.42	(0.16, 0.68)
		Synergy Index	5.32	(0.72, 39.11)		4.33	(0.59, 31.96)

‡Adjusted for age, gender, nodal OA, joint injury, occupational risk factors and bone mineral density (z-score). ^§Statistically significant with RERI <0, AP <0, and synergy index (SI) <1 indicating an antagonistic interaction. ^¶Statistically significant with RERI >0, AP >0, and SI >1, indicating a synergetic interaction. TGFβ1, transforming growth factor β1; SNP, single nucleotide polymorphism; BMI, body mass index; OA, osteoarthritis; OR, odds ratio; ORINT, odds ratio for interaction; LRT, likelihood ratio test; RERI, relative excess risk due to interaction; AP, attributable proportion.

ISSN: 1478-6362