A PGM1*1A variant with a reduced activity.

An adverse homozygosity at the phosphoglucomutase-1 (PGM1) locus was detected in a family by electrophoresis on starch gels. Isoelectric focusing on polyacrylamide gels could clearly demonstrate a faint band at the same position as that of PGM1 1A in the mother and the child. Further analysis of other family samples and densitometric evaluation of the stained bands revealed the genetic transmission of a variant allele with a reduced activity. The molecular basis for the low activity is still unknown.