The Plant and Animal Genome Conference PAG 2020, California, Amerika Birleşik Devletleri, 11 - 15 Ocak 2020, ss.1
Multiple signature-of-selection studies have identified single nucleotide polymorphism (SNP) rs426272889 as having been under extreme selection pressure in the recent evolutionary history of domestic sheep. However, no study had provided and explored phenotypic data suggesting a functional reason associated with this extreme selection. We tested rs426272889 for association with a panel of production traits in 779 U.S. Rambouillet, Targhee, Polypay, and Suffolk sheep. We identified association with mature weight at ages 3 and 4 years (P<0.05). This confirmed that sheep body size may be a primary reason for the extreme historical selection in this genomic region. The region surrounding SNP rs426272889 has had updated genomic annotation, and it is now identified in TMEM8B. Transmembrane protein 8B has little functional annotation in any mammalian species beyond a role inhibition of cancer cell proliferation. To our knowledge, this is the first study to link TMEM8B to body size under normal extensive production conditions. Additional work is required to identify the underlying functional variant or variants affecting body size. Once functional variants are identified, they may be used for selective breeding to improve sheep production.