Abstrait

Genetic polymorphism of candidate genes for fecundity traits in Egyptian sheep breeds

Ibrahim AH Barakat, Lamiaa M Salem, Niveen M Daoud, Wagdy KB Khalil, Karima F Mahrous

In reproductive planning, intervals between lambings, season, age of ewe, heat stress, nutrition state or breed are some of the factors which have a great effect on sheep fertility. Different mutations in the growth differentiation factor 9 (GDF9) and the bone morphogenetic protein 15 (BMP15) genes cause an increase in the ovulation rate in sheep. The aim of the current study was to determine the mutations in GDF9 and BMP15 genes and the probability of their effect on fertility in the major Egyptian sheep breeds. Blood samples were collected using EDTA from the Barki, Ossimi and Rahmani sheep breeds at different locations in Egypt, and DNA was then isolated using the salting out method. The PCR products of the genes were digested with MseI and DdeI restriction enzymes for the GDF9 gene, and with HinfI and DdeI for the BMP15 gene. The results showed that the PCR products digested with restriction enzymes exhibited a substitution in the G7 locus of the GDF9 gene in the Ossimi and Rahmani sheep breeds, and a substitution in the FecGH locus of the GDF9 gene in all sheep breeds. On the other hand, while the BMP15 gene loci digested only with HinfI showed mutations, this did not occur in all samples of the three Egyptian breeds. In conclusion, the BMP15 gene loci showed no polymorphism, while only the GDF9 gene loci were polymorphic in Barki, Ossimi and Rahmani sheep breeds.