Effect of Genetic Polymorphisms in GH/Hpa II and MSTN / Dra I Loci on Body Weight in Friesian Bull Calves.

OBJECTIVE

The GH and MSTN gene polymorphisms and their association with body weight were declared in a population of 100 Friesian bull calves.

MATERIALS AND METHODS

For DNA extraction, collection of blood samples was carried out from the studied animals. The PCR for GH and MSTN genes yielded fragments of 329 and 1346 bp, respectively.

RESULTS

The PCR-HpaII digestion of 329 bp of GH gene revealed three genotypes: AA genotype possess undigested fragment (329 bp), AB genotype has three fragments (329, 224 and 105 bp) and BB genotype has two fragments (224 and 105 bp). The GH genotypes incidence and alleles frequency were calculated. For the 100 Friesian bull calves, genotypic frequencies for the AA, AB and BB genotypes were 0.1, 0.78 and 0.12, respectively and the allele frequencies for A and B allele frequencies were 0.49 and 0.51. Statistical analysis revealed that there was a significant effect of GH genotypes on body weight. The AB genotype possessed higher body weight than the other 2 genotypes. Regarding MSTN gene, PCR-DraI digestion of 1346 bp fragment was monomorphic; where it yielded four fragments (505, 427, 321 and 93 bp) in all animals under study.

CONCLUSION

The outcome of this study is that it highlights the effectiveness of GH/HpaII locus as candidate marker for body weight in cattle rather than MSTN/DraI.