Relation between folate status, a common mutation in methylenetetrahydrofolate reductase, and plasma homocysteine concentrations. - Jacques,P.F.; Bostom,A.G.; Williams,R.R.; Ellison,R.C.; Eckfeldt,J.H.; Rosenberg,I.H.; Selhub,J.; Rozen,R. (Circulation, 1996)