Work

Sex-stratified genome-wide association analyses reveal sexually dimorphic genetic architecture of backfat thickness in pigs

Year: 2026

Type: article

Abstract: Sex influences the genetic architecture of complex traits, but its role in regulating backfat thickness (BFT) in pigs remains unclear. Here, we performed sex-combined and sex-stratified genome-wide association analyses in 2920 Duroc pigs (1460 females and 1460 entire males) using 6,320,080 imputed variants. Compared with the conventional sex-adjusted GWAS, sex-stratified analyses identified sex-specific loci, including a female-driven association region locus on SSC13 (~15.4 Mb) and a male-specific locus on SSC11 (~7.6 Mb), and revealed distinct allele-frequency and effect-size distributions between sexes. Candidate genes underlying these loci included RBMS3, MEDAG, TEX26, HSPH1 and B3GLCT. Moreover, sex-stratified genomic prediction achieved higher prediction accuracy, increasing prediction correlations from 0.652 to 0.723 in males and 0.757 in females, with cross-validated correlations increasing from 0.545 to 0.596 and 0.629, respectively. Collectively, these findings reveal the genetic basis of sexual dimorphism in BFT and provide new insights into the genetic dissection of dimorphic traits and livestock breeding.

Source: Genomics

DOI: 10.1016/j.ygeno.2026.111335