Bovine growth hormone gene polymorphism in Turkish indigenous breeds

In the present study it was determined that genotype and allele frequencies for bovine growthhormone gene polymorphisms of five Turkish indigenous breeds and one exotic breed by PCR-RFLPmethodology. A total of 125 genomic DNA isolated from five Anatolian breeds (YK-Anatolian Black,BI-Anatolian Grey, Ki- Kilis, AS- Anatolian Yellow, DAK- East Anatolian Red) and one exotic breed(SA-Siyah Alaca) were genotyped for bGH gene polymorphism. Three genotypes were obtained to theresult of Msp I digestion. Both alles was codominant so genotypes were entitled as AA, AB and BB.AB genotype was predominant when considered whole populations mean (0.63). Three breeds hadhigher frequency with regard to AB genotype (SA (0.95), Ki (0.85) and DAK (0.72)). BB genotypehad the lowest frequency among populations (0.06). Although all the Anatolian breeds had BBgenotype, it was absent in SA population. Overall allele frequencies of A and B were 0.628 and 0.372,respectively. The frequency of allele q in Ki (0.525), SA (0.475) and DAK (0.417) breeds was higherthan other breeds. The observed heterozygosity (Ho) was higher than the expected heterozygosity (He)for all of the breeds and for the population as a whole, Ho was above He (with a mean of 63 versus 47%), reflecting the elevated genetic variability in those populations. All of the populations were inaccordance with HWE, except Ki and SA (p<0.01 and p<0.05). Statistical results showed that genefrequency of allele B was depend on breeds (p=0.0209). There was a significant association betweenpolymorphic allele (B) frequency and breeds. There were differences between Ki-AS, Ki-BI, SA-AS,SA-BI (p<0.01 and p<0.05) and DAK-BI (p<0.05) breeds when they were compared forpolymorphism. Ki and SA were differed from other breeds and took place in with high frequencygroup according to comparison result.In the previously studies, it was shown that B allele was orginated from B. indicus andresponsible for high milk production. It could be said that those three breeds (Ki, SA and DAK) hadhigher proportion of B. indicus genes than others. It was known that Ki and SA breeds had highermilk production than others, as well. That study showed that it was worth to research associationbetween milk traits and bGH locus polymorphism in another study.The present study showed that genetic variations of five Anatolian indigenous breeds and oneexotic breed (SA) for bGH gene polymorphism.Key Words: Bovine growth hormone gene polymorphism, Anatolian indigenous breeds, PCR-RFLP.II