Investigation of polymorphisms on ABCG2 and AA-NAT genes in different sheep breeds in Bulgaria

Ivona Dimitrova, Nikolay Petrov, Milena Bozhilova-Sakova

Abstract: The present study was conducted in order to investigate and identify the polymorphism in two sheep genes – ABCG2 (associated with milk production) and AA-NAT (associated with seasonality of reproduction) in 6 breeds, raised in Bulgaria. Blood samples were taken from 42 animals of Karnobat Merino, Caucasian Merino, Northeast Bulgarian Merino, Il de France, Karakachan and Askanian Merino. Genomic DNA was extracted and genotypes were estimated by means of PCR amplification and PCR-RFLP method. After PCR amplification and electrophoretic analysis two alleles and three genotypes for ABCG2 were revealed. The genotypes of AA-NAT gene in all investigated animals were established using RFLP (restriction fragment length polymorphism) analysis with use of Smal restriction enzyme. There is polymorphism in AA-NAT locus of investigated animals from Askanian Merino, Karnobat Merino, Caucasian Merino and Northeast Bulgarian Merino breeds which could be used in future investigations referring to candidate genes for seasonality of sheep reproduction. AA-NAT locus is monomorphic in investigated animals from II de France and Karakachan breeds – the allele G and the genotype GG were detected. The ABCG2 locus of Askanian Merino, Karnobat Merino, Northeast Bulgarian Merino and Il de France animals is monomorphic, but in these of Caucasian Merino and Karakachan was found to be polymorphic. This represents the first study of the ABCG2 and AA-NAT genes in sheep breeds reared in Bulgaria.

Keywords: AA-NAT gene; ABCG2 gene; breeds; polymorphism; sheep

Date published: 2019-09-05