Starch gel electrophoresis for galactose-1-phosphate uridylyl-transferase applied to dried filter paper blood specimens.

Starch gel electrophoresis of galactose-1-phosphate uridylyl transferase has been adapted for use on dried filter paper blood specimens submitted for the purposes of routine newborn screening for galactosemia and other inborn errors of metabolism. Selected for study were those specimens with reduced transferase activity, as determined by the Beutler enzyme spot screening test. Clinically benign low activity enzyme variants were readily identified, thus reducing significantly the number of requested additional blood specimens. Transferase-deficient specimens with potential clinical significance had too little activity for transferase visualization and thus could be separated from the benign variants. This technique would facilitate routine newborn screening for galactosemia.