PRENATAL-DIAGNOSIS BY MINISATELLITE ANALYSIS IN ITALIAN FAMILIES WITHPHENYLKETONURIA

A polymorphic short tandem repeat (STR) in intron 3 (Goltsov et al, 19 93) and a variable number of tandem repeats (Hind III-VNTR) flanked by two constant Hind III sites (Goltsov et al., 1992) have been recently identified in the human phenylalanine hydroxylase (PAH) gene. These p olymorphisms are easily detected by the polymerase chain reaction (PCR ) and gel electrophoresis. We report on the use of these two novel pol ymorphisms in three Italian families with pregnancies at risk for clas sical phenylketonuria (PKU). A carrier status for PKU was ascertained in two fetuses; the third family refused prenatal diagnosis, although informativeness was shown to be complete.