Molecular analysis of the length polymorphic <i>MUC1</i> gene in cattle

Abstract

Summary A study was undertaken to sequence the overall repetitive region of the bovine MUC1 gene, to elucidate its structure in terms of number of repetitions, and to examine its relationship to the polymorphic epithelial mucin expressed on the milk fat globule membrane. A polymerase chain reaction protocol was developed to detect MUC1 polymorphism. Four different alleles were found in samples from Italian Friesian and Piedmontese cattle breeds. The alleles ranged from 778 bp to nearly 1600 bp, and size differences between alleles were due to variable numbers of 60 bp imperfect repeats. MUC1 gene polymorphism was closely related to milk fat globule mucin variation. Moreover, on the basis of the complete gene sequence, it was possible to predict an overall core protein that may be a highly O‐glycosylated molecule, in accordance with the size of the milk fat globule mucin fractions.