Inborn Errors of Folate Metabolism

(First of Two Parts) SINCE 1961, five and possibly six new disorders have been attributed to congenital defects in the uptake or utilization of folic acid, an essential vitamin in man. Although these disorders are still considered rare, the number of patients has nearly doubled in the past two years. Interest in this group of disorders stems from the likelihood that they may result in serious neurologic impairment, from the possibility that they will respond to therapy with folates, and from their potential contribution to an understanding of human folate metabolism. Considered here are the features and implications of the….