Risk of Down syndrome conferred by MTHFR C677T polymorphism: Ethnic variations

(w ww .m ed kn ow .co m) . P=0.018), while no signifi cant difference in maternal transmission was observed (χ2 =3.33, P=0.068). No difference in allelic frequencies was observed (χ2 =0.065, P=0.968) between DS mother (n=68; C=0.846, T=0.154) and control mother (n=59; C=0.839, T=0.161). An earlier report from Varanasi (25.33°N, 83°E),[4] a north-eastern state of India, had shown strong association of 677T with Indian DS patients and 677T allele was considered as a risk factor for DS contributed by either parent. However data obtained in our study, based on eastern Indian population, do not support the conclusions made by earlier investigators; allelic frequencies were not much different in parents of DS patients as compared to controls. Any preferential transmission of T allele was also not observed.