New Genetic Variants of Parotid Salivary Amylase

Abstract

Isoelectric focusing can reveal at least 2 heterozygotes of the Amy1R class of variants. Family data on these variants show codominant inheritance for both alleles with respect to the normal Amy1A allele. The frequencies of the alleles Amy1R1 and Amy1R2 in the Dutch population (n = 144) were 0.06 and 0.03, respectively. Electrophoretic analysis of whole parotid saliva from different Amy1R phenotypes and of purified normal and Amy1R1 gene products indicates that the variant proteins differ from the normal protein by enhanced deamidation of Aspn and/or Gn residues.