Detection of single nucleotide polymorphisms at major prolificacy genes in the Mehraban sheep and association with litter size

Abstract

the present study aimed to investigate the presence of polymorphisms at four known genes controlling ovine prolificacy i.e. BMP15, GDF9, BMPR1B and B4GALNT2 in a sample of 115 iranian Mehraban ewes and their association with litter size (LS) and lambs' birth weight (BW) traits. Using Sanger sequencing of exons and polymorphism specific genotyping, ten SNPs (Single Nucleotide polymorphisms) were observed in only two genes, GDF9 and BMPR1B. Seven SNPs were found in the GDF9 gene on the chromosome 5. Among them, six were already described in the coding sequence, and a new one (g.41840985C>T) was found in the 3'UTR. In the BMPR1B gene on the chromosome 6, three novel SNPs were detected in the exon 7 (g.29382184G>A; g.29382337G>A and g.29382340G>A). Allelic frequencies were established for six SNPs among the ten identified and they were in Hardy-Weinberg equilibrium. A significant association was found between the novel snps found in the exon 7 of BMPR1B and LS. Present results indicate the potential role of the BMPR1B locus in controlling prolificacy of Mehraban sheep and provide genetic markers for further exploitation in selection to improve reproductive efficiency.

The high prolificacy of D’man sheep is associated with the segregation of the FecLL mutation in the B4GALNT2 gene

“…Additionally, we also sequenced the exon 7 of BMPR1B to genotype for the Booroola mutation ( FecB B , OAR6:29382188A>G, NC_019463.1; Mulsant et al, ). The FecB B prolific allele was absent, but we have observed the recently evidenced SNP (OAR6:29382337G>A) shown to be associated with prolificacy in the Iranian Mehraban breed (Talebi et al, ). As shown in the Table , even if A/A ewes exhibited a lower mean LS (1.68 ± 0.49, n = 6) than G/A (1.97 ± 0.45, n = 5) or G/G ewes (2.22 ± 0.19, n = 3), no significant association was evidenced with the prolificacy of these D'man ++ ewes.…”

“…Additionally, we also sequenced the exon 7 of BMPR1B to genotype for the Booroola mutation (FecB B , OAR6:29382188A>G, NC_019463.1; Mulsant et al, 2001). The FecB B prolific allele was absent, but we have observed the recently evidenced SNP (OAR6:29382337G>A) shown to be associated with prolificacy in the Iranian Mehraban breed (Talebi et al, 2018). As shown in the breeds (those with improved traits) were first selected in south-west Asia and then spread into Europe, Africa and the rest of Asia (Chessa et al, 2009).…”

“…At the B4GALNT2 locus, the genotyping of FecL L ( B4GALNT2 intron 7, OAR11:36938224T>A, NC_019468.1, Drouilhet et al, ) was obtained by a first step of KAPA Blood PCR amplification of a specific fragment encompassing the mutation position (KAPA Biosystems) and a second step of fluorescent Kompetitive Allele Specific PCR via the KASP V4.0 2× Master mix (LGC genomics) as already described (Chantepie et al, ). KAPA Blood PCR amplification was also used for subsequent DNA sequencing as described (Talebi et al, ) of exons 1 and 2 of BMP15 and GDF9 , and exon 7 of BMPR1B . Obtained reads were aligned against the ovine reference sequence for each gene of interest (ovine reference genome v3.1; BMP15 : NC_019484.1; GDF9 : NC_019462.1 and BMPR1B : NC_019463.1) using CLC Main Workbench Version 7.6.4 (http_blank://www.clcbio.com) in order to assess for polymorphisms.…”

Genomic Signatures of Selection Associated With Litter Size Trait in Jining Gray Goat

“…It has been suggested that the members of transforming growth factor-β (TGF-β) superfamily, including BMPR-1B, BMP15, and GDF9, affected the ovulation and LS (Demars et al, 2013). Also, numerous studies had explored the polymorphisms of these genes in sheep and goat breeds (Ahlawat et al, 2016;Talebi et al, 2018). Here, we identified large amounts of SNPs in Jining Gray goat, and more than half were novel sites, all the abundant variants extended genetic resource in goat for fecundity traits associated research.…”

“…Previously, more attentions have been attracted in reproductive trait study of sheep, four major prolificacy (that is LS) genes have been identified, that are bone morphogenetic protein receptor 1B (BMPR1B, FecB), bone morphogenetic protein 15 (BMP15, FecX), growth differentiation factor 9 (GDF9, FecG), and beta-1,4-N-acetyl-galactosaminyl transferase 2 (B4GALNT2, Fec L ) (Polley et al, 2010;Drouilhet et al, 2013;Våge et al, 2013;Abdoli et al, 2016). In particular, it has been proved an extra ovulation increased per estrus for one copy of BMP15 (0.4) and BMPR-1B (1.5) mutation (Davis, 2005;Abdoli et al, 2016;Talebi et al, 2018). Actually, the mutations of GDF9 and BMP15 genes had been verified to be strongly associated with LS trait in sheep (Demars et al, 2013;Våge et al, 2013).…”