The existence of major genes affecting fecundity in sheep flocks throughout the world has been demonstrated.Three major genes whose mutations can increase ovulation rate have been discovered,and all related to the tra...The existence of major genes affecting fecundity in sheep flocks throughout the world has been demonstrated.Three major genes whose mutations can increase ovulation rate have been discovered,and all related to the transforming growth factorβ(TGF-β)superfamily.The mutant FecB of bone morphogenetic protein receptor 1B(BMPR1B)has an additive effect on ovulation rate.Six mutations(Fec^(XI),Fec^(XH),Fec^(XG),Fec^(XB),Fec^(XL),Fec^(XR))of bone morphogenetic protein 15(BMP15)related with fertility have been identified that share the same mechanism.All the mutants can increase ovulation rate in heterozygotes and cause complete sterility in homozygotes.Homozygous ewes with two new mutations(FecX^(Gr),FecX^(O))of BMP15 had increased ovulation rate without causing sterility.There are five mutations in growth differentiation factor 9(GDF9)associated with sheep prolificacy where FecG^(E) and FecG^(F) have additive an effect on ovulation rate and litter size.The newly identifiedβ-1,4-N-acetylgalactosaminyltransferase 2(B4GALNT2)gene of FecL is proposed as a new mechanism of ovulation rate regulation in sheep.Woodlands is an X-linked maternally imprinted gene which increases ovulation rate.In addition,several putative major genes need to be verified.This review is focused on the identification of the mutations and mechanisms whereby the major genes affecting ovulation rate.展开更多
基金This work was funded by the Agricultural Science and Technology Innovation Program of China(ASTIP-IAS13)Key Technology Research and Development Program of Xinjiang Uygur Autonomous Region of China(200891102 and 2013911056)the Earmarked Fund for China Agriculture Research System(CARS-39).
文摘The existence of major genes affecting fecundity in sheep flocks throughout the world has been demonstrated.Three major genes whose mutations can increase ovulation rate have been discovered,and all related to the transforming growth factorβ(TGF-β)superfamily.The mutant FecB of bone morphogenetic protein receptor 1B(BMPR1B)has an additive effect on ovulation rate.Six mutations(Fec^(XI),Fec^(XH),Fec^(XG),Fec^(XB),Fec^(XL),Fec^(XR))of bone morphogenetic protein 15(BMP15)related with fertility have been identified that share the same mechanism.All the mutants can increase ovulation rate in heterozygotes and cause complete sterility in homozygotes.Homozygous ewes with two new mutations(FecX^(Gr),FecX^(O))of BMP15 had increased ovulation rate without causing sterility.There are five mutations in growth differentiation factor 9(GDF9)associated with sheep prolificacy where FecG^(E) and FecG^(F) have additive an effect on ovulation rate and litter size.The newly identifiedβ-1,4-N-acetylgalactosaminyltransferase 2(B4GALNT2)gene of FecL is proposed as a new mechanism of ovulation rate regulation in sheep.Woodlands is an X-linked maternally imprinted gene which increases ovulation rate.In addition,several putative major genes need to be verified.This review is focused on the identification of the mutations and mechanisms whereby the major genes affecting ovulation rate.
