Multiple morphological abnormalities of the sperm flagella (MMAF)-associated genes: The relationships between genetic variation and litter size in goats.

Abstract

Several genes are associated with the multiple morphological abnormalities of the sperm flagella (MMAF) syndrome, including QRICH2, CFAP43, CFAP44, CFAP69, CCDC39, and AKAP4 genes. Although previous work has shown that these genes are significantly associated with male reproductive traits in certain species, it is not yet known whether they are associated with reproductive traits in the goat. In this study, we investigated the correlations between 47 putative indel mutations in MMAF- associated genes, and first-born litter sizes in 1479 Shaanbei white cashmere (SBWC) goats. Our analysis showed that five of these indel mutations were polymorphic: QRICH2-P4, CFAP43-P20, CFAP69-P4, CFAP69-P6, and CFAP69-P7. Association analysis revealed that only a 6-bp indel variation within CFAP43 (CFAP43-P20) was strongly significantly associated with litter sizes in SBWC goats (P=0.000). We also identified a significant difference in the genotypic distribution between the mothers of single lambs and the mothers of multiple lambs (P=0.001); carriers of the DD genotype had greater litter sizes than carriers of the II or ID genotype. Our analysis also revealed 8-bp and 6-bp indels in CFAP69 (CFAP69-P4 and CFAP69-P6, respectively) that were in complete linkage disequilibrium with each other (D'=0.99, r2=1.00). These findings indicate that the 6-bp indel mutation in the CFAP43 gene can be used as an effective molecular marker for selecting reproductive traits in goat breeding operations.