Population cytogenetics of autosomal fragile sites.

The present investigation deals with a population chromosomal survey for autosomal fragile sites under conditions of folate deprivation in 405 mental retardates. A total of 13 ascertainments of folate sensitive autosomal fragile sites is observed, of which 10q23 fragility appears to be the most frequent. Further cytogenetic studies of normal and retarded individuals are required to help elucidate the possible phenotypic effect of these autosomal sites and mental retardation.