Mutations in BMPR-IB and BMP-15 genes are associated with litter size in Small Tailed Han sheep (Ovis aries)1

Abstract

The Small Tailed Han is a prolific local sheep breed in China. The bone morphogenetic protein receptor IB (BMPR-IB) gene, which affects the fecundity of Booroola Merino sheep, and the bone morphogenetic protein 15 (BMP-15) gene, which affects the fecundity of Inverdale, Hanna, Belclare, Cambridge, and Lacaune sheep, were studied as candidate genes associated with the prolificacy of Small Tailed Han sheep. Single nucleotide polymorphisms of BMPR-IB and BMP-15 genes were detected in Small Tailed Han ewes (n = 188) by PCR-RFLP. The combined effect of the 2 genes on the prolificacy of Small Tailed Han sheep was studied. The results indicated that the same FecB mutation (Q249R) occurred in the BMPR-IB gene in Small Tailed Han ewes as found in Booroola Merino ewes. The Small Tailed Han ewes with genotypes FecB(B)/FecB(B) and FecB(B)/FecB(+) had 1.40 (P < 0.01) and 1.11 (P < 0.01) more lambs, respectively, than those with genotype FecB(+)/FecB(+). The same FecX(G) mutation (Q239Ter) of the BMP-15 gene was found in Small Tailed Han ewes as in Belclare and Cambridge ewes. The Small Tailed Han ewes with the heterozygous mutant FecX(G)/FecX(+) had 0.55 (P < 0.01) more lambs than those with the wild-type FecX(+)/FecX(+). The Small Tailed Han ewes carrying mutations in both BMPR-IB and BMP-15 genes had greater litter size than those with either mutation alone. In view of our results, marker-assisted selection using both BMPR-IB and BMP-15 genes is warranted to increase litter size in sheep and will be of considerable economic value to sheep producers.

Using sheep lines with mutations in single genes to better understand ovarian function

“…Although a mutation in the BMPR1B gene has been identified in several sheep lines selected for increased fecundity (Davis et al 2002, Chu et al 2007, the same mutation (Mulsant et al 2001, Souza et al 2001, Wilson et al 2001 has been observed in each of these lines. In contrast to the relatively restricted expression of the GDF9 and BMP15 genes, BMPR1B is widely expressed throughout the body and the mutation likely subtly affects multiple tissue types including the pituitary and the adrenal glands (Wilson et al 2001, Xu et al 2010).…”

“…The AA genotype had a larger litter size than the AB genotype, suggestive of higher ovulation rates in the homozygous vs the heterozygous carriers. However, interpretation of these data sets is complicated by the lack of any animals with the BB genotype, potentially due to the rarity of the B allele, and the knowledge that mutations in both BMP15 and BMPR1B are also present, but not fixed, in the Small Tailed Han sheep (Davis et al 2006b, Chu et al 2007). …”

Application of PCR-RFLP technique to determine Booroola gene polymorphism in the Sangsari sheep breed of Iran

“…New findings indicated that multiple births in sheep bearing the Booroola gene (FecB) are a result of chromosome 6 mutation in a part comprising bone morphogenic protein receptor gene IB (BMPR-IB) (1,4,(13)(14)(15). The BMPR-IB gene encodes the morphogenic growth factor βs.…”

Sakız Irkı Koyunlarda FecB, BMP15 ve CAST Genlerindeki Mutasyonların Analizi

“…In general, heterozygous ewes with mutations in both FecB and FecX G exhibited increased fertility compared with ewes harboring a mutation in only one of these genes [6] . The Galway mutation has been identified in Cambridge [16] , Garole, Kendrapada [12] and Small Tailed Han sheep [19] . Hanrahan et al [16] estimated the effect of FecX G to be 0.77 and 1.18 in Belclare and Cambridge ewes, respectively.…”