Galactosaemia appears to be one of the most appropriate disorders for
routine newborn screening as almost normal outcome can be achieved in
most of the identified cases. Galactose and galactose-1-phosphate were
determined using Guthrie cards in a commercial kit based on a colorim
etric microassay. Among 199 642 newborns, nine cases with classic gala
ctosaemia, three with epimerase deficiency, six with compound Duarte(2
)/heterozygotes for galactosaemia and four with compound(2) Duarte hom
ozygosity were found. Even though the number found among the screened
neonates is small because it is such a rare disease, our results indic
ate one of the highest frequencies of the disease ever reported.