Mutations in inhibin alpha gene and their association with litter size in Kalahari Red and Nigerian goats

This study was conducted to identify SNPs in inhibin alpha (INHA) gene and investigate their association with litter size in two Nigerian goat breeds {West African Dwarf (WAD, n = 226), Red Sokoto (RS, n = 70)} and Kalahari Red (KR, n = 70). Sequence analyses revealed four SNPs {g.−65C > G/rs643347356 (5'UTR), g.2518G > A (a novel variant in exon 2), g.3041A > G/rs641311609 (exon 3) and g.3234C > T/rs670889338 (3'UTR)}. Homozygous wild type CC at g.−65C > G and GG at g.2518G > A loci were predominant genotypes in Kalahari Red goats. CC was the predominant genotype in all the three breeds at g.3234C > T locus and the frequency of allele C was 0.88, 0.98 and 0.98 in WAD, RS and KR populations respectively. Allele diversity index was low (He < 0.3) in the three breeds at g.−65C > G, g.2518G > A and g.3234C > T loci. WAD and KR goats had moderate genetic diversity (0.25 ≤ PIC ≤ 0.5) at g.3041A > G locus. Pair-wise comparison revealed that does having CT genotype at g.3234 C> T locus had significantly (P = 0.01) larger litter size compared with CC in WAD goats, while SNP genotype at other loci were not significantly associated with litter size.