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The aim of this study was to determinate allele frequency β-lactoglobulin in Pramenka breed sheep in Bosnia and Herzegovina. The DNA was extracted from blood of 283 sheep, collected from four flocks around Sarajevo, Bosnia and Herzegovina. The gene β-lactoglobulin was amplified using polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP) technique. Two genetic variants (A and B) and three genotypes (AA, AB and BB) of β-lactoglobulin have been identified. Genotype frequencies of β-lactoglobulin were with the following values: AA (0.325), AB (0.445), and BB (0.229), while the frequencies of allele A and B were 0.547 and 0.453 respectively. The highest frequency of genotype AA is present in the location Treskavica (38%), genotype AB in the location Vlašić (52%), while the genotype BB is mostly present in location Bjelašnica (29%). The population of Pramenka breed sheep was in Hardy-Weinberg equilibrium. It is expected that in a future the programs in sheep breeding in Bosnia and Herzegovina certainly would take into account the genetic variants of β-lactoglobulin that could contribute to better production and economic benefit. [ABSTRACT FROM AUTHOR]

Abstract: Different biogeographical and sociocultural conditions have contributed to develop several West Balkan native sheep populations, most of which are considered as different types of Pramenka sheep. These populations have a wide variety of phenotypes that indirectly indicate a quite high level of genetic variability. Here, we analyzed agouti signalling protein (ASIP) and melanocortin 1 receptor (MC1R) gene polymorphisms in two Pramenka sheep populations (Dubian and Privorian) originated in Bosnia and Herzegovina in which coat colours and colour patterns are not fixed traits and evaluated association between these genes and coat colours of the investigated sheep. All genotyped animals carried only wild type MC1R haplotypes and no association between variability of this gene and coat colour was observed. Association between the absence of duplicated ASIP copy allele and almost complete dark (black/grey) coat colour was highly significant (Fisher exact test: P =5.872E−09). These results confirmed the role of the Agouti locus in affecting coat colour in sheep. The six animals with complete concordance between absence of duplicated copy allele and extended black/grey coat colour may be homozygous for recessive nonagouti black alleles (A a ), as indicated in other breeds. Despite the highly significant association observed between absence of duplicated allele and extended dark coat colour in these Pramenka sheep, association was not complete. One Dubian sheep with the same coat colour phenotype was heterozygous with a duplicated and a non duplicated allele. Moreover, spotted black regions were present in all animals carrying at least a duplicated ASIP allele. These results indicated that other genetic factors or mechanisms (additional uncharacterized ASIP alleles, other loci, or epistatic interaction with other genes) might be involved in affecting coat colours (white vs dark) and different spotted patterns in sheep. This study could represent an example of eploitation of native genetic resources to identify and verify association between DNA markers and phenotypic traits. [Copyright &y& Elsevier]