Rabbit Growth Hormone and Myostatin Gene Polymorphisms

The aim of the present research was to investigate two rabbit populations from the New Zealand White breed and to identify single nucleotide polymorphisms with respect to the genes encoding growth hormone (GH) and myostatin (MSTN) by PCR-RFLP assay. Genotype profiles were established in a total of 50 rabbits from two populations: one reared at The Institute of Animal Science, Kostinbrod (NZW-KB, n= 26) and another (NZW-SZ, n=24), reared at the Experimental farm of the Faculty of Agriculture, Trakia University, Stara Zagora. As expected, a 231bp fragment of the polymorphic site (part of the 5ʹ-flanking region, 5ʹ-untranslated region and exon 1) of GH gene and a80 bp fragment of the intron 2of MSTN gene were amplified using PCR and digested with endonuclease enzymes Bsh1236 and Alu I, respectively. The obtained restriction fragments revealed three genotypes: CC, CT and TT for the GH gene, observed in 27%, 62%,and 11% of the NZW-KB rabbit population and in 42%, 50%,and 8% of the NZW-SZ population, respectively, without departure from the Hardy-Weinberg equilibrium (P>0.10) in these groups. The allele frequencies determined a prevalence of the C allele (0.577 and 0.667) over the T allele (0.423 and 0.333) in both populations. This tendency was preserved with regard to MSTN gene, where the frequency of the C allele (0.692 and 0.813) was higher than that of the T allele (0.308 and 0.187). The homozygous genotype TT was absent in the investigated rabbit populations. The observed heterozygosity value (0.615) in NZW-KB rabbit population was higher compared to the expected one (0.426) resulting in deviation from Hardy-Weinberg Equilibrium (P<0.1), in contrast to the NZW-SZ population. The results from the present investigation confirmed the presence of the polymorphisms in GH and MSTN genes. Therefore, the genetic variability established in these polymorphic loci could be applied in further association studies with growth and meat production traits in rabbits.