Evidence for a 'silent allele' GLO0 at the glyoxalase I locus

In a three-generation family, the segregation of an apparent silent allele at the GLO I locus in association with the rare HLA haplotype 'AW30-CW4-BW35' was observed in four members. In two cases the assumption of homozygosity at the GLO locus would lead to mother-child exclusions. Phenotypically, the GLO activity in the GLO0 carriers is clearly diminished.