Gene-Gene Interactions in the Folate Metabolic Pathway and the Risk of Conotruncal Heart Defects

Table 3

Case-only results (unadjusted P values) for all pairwise combinations of maternal genotypes and CTRD, Children’s Hospital of Philadelphia, 1997–2007.

	BHMT	CBS	DHFR	MCP1	MTHFR	MTHFR	MTR	MTRR	SHMT	TCN2
	G742A	844ins68	19-bp del	A251G	C677T	A1298C	A2756G	A66G	C1420T	C777G
BHMT G742A		0.95	0.64	0.71	0.15	0.56	0.92	0.06	0.38	0.92
CBS 844ins68			0.28	0.98	0.01	0.02	0.94	0.65	0.27	0.36
DHFR 19-bp del				0.95	0.41	0.59	0.14	0.81	0.14	0.17
MCP1 A251G					0.71	0.65	0.64	0.75	0.83	0.19
MTHFR C677T						N/A*	0.97	0.41	0.57	0.58
MTHFR A1298C							0.57	0.14	0.48	0.74
MTR A2756G								0.42	0.57	0.92
MTRR A66G									0.92	0.28
SHMT C1420T										0.43

^∗This interaction was not assessed as the two MTHFR variants are in strong linkage disequilibrium.