Genome‐wide epistatic interactions of litter size at birth in Chinese indigenous pigs

Abstract

Summary Improving litter size at birth (TNB) and the number of piglets born alive (NBA) are the main breeding goals related to litter traits, which are economically important. A better understanding of genetic architecture underlying TNB and NBA traits could increase pig production efficiency. However, most previous studies on these traits focus on additive genetic effects, while epistatic interactions underlying TNB and NBA traits has not yet been well investigated, which are essential to understand how traits‐related genes interact. Herein, we conducted genome scans of epistatic interactions underlying TNB and NBA traits in a total of 150 Chinese indigenous pigs (75 Jinhua and 75 Shengxian Spotted pigs) with high throughput genomic data. Based on SNPs with high interaction values and connectivity scores, we identified eight promising candidate genes (AKT2, TSC1, MTOR, PIK3R5, TIAM1, FGF14, RALB and ROR2) potentially associated with litter traits in pigs. Moreover, the underlying pathways, e.g., calcium ion transport, pointed out their roles in litter size‐related traits. Our findings provide new insight into genetic architecture of litter traits in pigs and will benefit economic profits in pig production.

Identification of Signatures of Positive Selection That Have Shaped the Genomic Landscape of South African Pig Populations

“…For example, PIK3R5 is one of the genes identified in the O.R. Tambo population that influences litter size at birth and the number of piglets born alive [70], which is important as pigs differ greatly in litter size. For example, the wild boar sows an average if 6.6 litters [71] per year versus an average of 14 to 15.3 litters per sow in Large White breeds [72,73], while indigenous breeds such as Kolbroek average at 810 piglets [74].…”

GWAS of Reproductive Traits in Large White Pigs on Chip and Imputed Whole-Genome Sequencing Data

“…The ZDHHC14 gene may act as a marker and target for the clinical diagnosis and treatment of pre-eclampsia [ 58 ]. The FGF14 gene may be a promising candidate gene associated with litter traits in pigs [ 59 ] and a potential candidate gene for teat number trait in Duroc pigs [ 60 ]. The BAIAP2L1 gene may serve as a biomarker in ovarian cancer [ 61 ].…”

Heterozygosity and homozygosity regions affect reproductive success and the loss of reproduction: A case study with litter traits in pigs

“…Litter traits are one of the most important traits for breeding in pig production [1] , [2] . Improving total number born ( TNB ) and number born alive ( NBA ) traits are of great interest as enhancing the economic profit, and become the main breeding goals in the modern pig industry [1] , [3] . Meanwhile, sow reproductive performances are limited by embryonic mortality and fetal losses during the pregnancy period [4] .…”