Characterization of a single nucleotide polymorphism in the coding sequence of the bovine transferrin gene

Abstract

A single nucleotide polymorphism was identified in the coding sequence of the bovine transferrin gene. Two alleles (SSCP1 and SSCP2) were detected by SSCP analysis and the mutation point was identified and confirmed by direct sequencing of the PCR products. The relationship between protein and DNA polymorphism was established. Protein variants A, D₁ and E correspond to SSCP allele 1 and variant D₂ corresponds to SSCP allele 2. DNA sequences from genotypes AA, AE, AD₂, D₁E, D₂E and D₂D₂ reveal an A/G substitution at position 1455 of the cDNA which causes a Gly/Glu substitution which could be responsible for the mobility difference between D₁ and D₂ variants. Because of the number of variants, this suggests that other SNPs exist in the bovine transferrin gene. A linkage analysis between the SSCPs and two microsatellites (UWCA46 and CSSM019) mapped the transferrin gene to BTA1. Two-point analysis revealed a tight linkage within the transferrin protein variants and the SSCPs.