Evidence for association of lymphoid enhancer-binding factor-1 (LEF1) with the number of functional and inverted teats in pigs

Abstract

The lymphoid enhancer-binding factor-1 (LEF1) belongs to a family of regulatory proteins that share homology with the high mobility group protein-1 (HMG1). The LEF1 gene is a mediator in the canonical Wnt-signalling pathway required for morphogenesis of early mammary gland during embryogenesis. Here we describe the molecular characterisation of the porcine LEF1 gene and its association with number of teats and inverted teats in experimental and commercial populations. The 2357-bp cDNA sequence contains an 1197-bp open reading frame encoding a protein of 398 amino acids. The porcine LEF1 protein shares high identity with LEF1 in other mammalian species. The LEF1 gene contains 12 exons and maps to pig chromosome 8 (SSC8). We identified two single nucleotide polymorphisms (SNPs), a T1351C transition and an A1666C transversion, in the 3′ end of LEF1. Associations of the SNP A1666C with presence of inverted teats (P≤ 0.01), total number of teats (P ≤ 0.01) and total number of inverted teats (P ≤ 0.01) were highly significant; SNP T1351C showed near significance with total number of inverted teats (P ≤ 0.1) in the experimental DUMI population. SNP T1351C was significantly associated with total number of inverted teats (P= 0.04) and close to significance with affected teats (P = 0.06) in commercial populations. Haplotype analysis confirmed the tendency towards association with affected teats (P = 0.06) in the experimental DUMI population. The function, position, and associations shown here promote LEF1 as a candidate gene for number of teats and in particular for presence and number of inverted teats.