Galactosemia as a result of galactose-1-phosphate uridyltransferase deficiency.

This study was designed to determine the activity of galactose-1-phosphate uridyltransferase enzyme in a family (parents and eight children): four of these with clinical diagnosis of classical galactosemia. In two of them a complete transferase deficiency was found, thus confirming diagnosis; the other two, a pair of dizygotic twins, who since birth up to 11 years of age had been on a galactose free diet, showed enzymatic activity consistent with normal heterozygotes, one of them, and with normal homozygotes, the other. The parents and four brothers had the same enzyme activity levels an those found in heterozygotes for galactosemia. Early diagnosis is of utmost importance in classical galactosemia, and we emphasize this point because patients can be treated with dietotherapy and primary prevention is possible through genetic counseling.