PRNP gene polymorphisms in main indigenous Turkish goat breeds.

The polymorphisms of the PRNP gene influence the susceptibility to scrapie in goats. In this study, caprine PRNP gene was analysed in a total of 249 individuals from three main indigenous goat breeds of Turkey: Anatolian Black, Angora and Kilis. We focused on the Anatolian Black breed, which represents 97% of the goat population in Turkey and compared the data of samples originated from different geographical regions. Eight polymorphisms were determined, given rise to 12 haplotypes. Allele, genotype and haplotype frequencies of the polymorphisms at codons 142, 143, 146, 154, 171, 211, 222 and 240 were calculated. Alleles associated to resistance to scrapie were found to be relatively rare in all breeds. The resistance allele 222K was absent in Turkish breeds. Other resistance-associated alleles: 146D, 146S, 154H and 171R were observed with low frequencies. The results of this study, which cover the mainly bred indigenous goats in Turkey, present the distribution of PRNP polymorphisms. Very low frequencies of resistance-associated alleles show the susceptibility to scrapie. The resistance-associated alleles S and D of codon 146 might be accepted as candidate alleles, due to their relative higher frequencies observed in the present study. A breeding program aiming to increase particularly the frequency of 146S might be applied. Predictions about impacts of a long-term breeding programme based on low initial allele frequencies and regarding its possible adverse effects are warranted. Our results might be a database for future breeding programmes, which should be carefully designed with adequate levels of genetic resistance and acceptable timeframe.

FASN gene polymorphism in indigenous cattle breeds of Turkey.

The aim of this study was to determine the variants of the thioesterase (TE) beta-ketoacyl reductase (KR) domains of the Fatty Acid Synthase (FASN) gene, in the East Anatolian Red (EAR) and South Anatolian Red (SAR) cattle breeds. It has been suggested that the FASN gene is effective on fatty acid composition of meat in cattle. In this study, the genotype and allele frequencies of g.17924 A>G, g.18440 G>A and g.16024 G>A, g.16039 T>C in TE and KR domains, respectively, were detected by using polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP) method. The g.18663 T>C polymorphism of the TE domain was determined by direct sequencing. The GG genotype of the g.17924 A>G polymorphism, which affects unsaturated fatty acid composition positively, has a high frequency in EAR and SAR breeds. The frequencies of the two haplotypes g.16024 G>A and g.16039 T>C in the KR domain were found to be significantly high in both breeds. These haplotypes also have positive effects on unsaturated fatty acid composition. The AA genotype of the g. 18440 G>A polymorphism, which is suggested to be absent in Bos taurus breeds, was detected in SAR and EAR breeds with frequencies close to those in Bos indicus breeds. In conclusion, we suggest that SAR and EAR cattle breeds have an advantage in terms of genotype and haplotype distribution of the polymorphisms in TE and KR domains of the FASN gene. Additionally g.18440 G>A polymorphism might be a potential marker for breed discrimination.