Abstract

The Retinta Extremeña goat is a well-adapted breed to "Dehesa" environment. Traditionally their raw milk is used to make artisan cheese. However, crosses with specialized breeds are occurring since the eighties, this goat breed has been declared of special protection by the Spanish Agriculture Ministry (R.D. 1682/1997 and R.D. 229/2008). Genetic studies about casein variants have been mainly performed on Spanish goats of high milk yields because the caseins are a relevant fraction of milk. But recent studies claimed to study the caseins in all breeds, including threatened goat breeds to decide about its conservation value. This study was focused on the aS1-casein in the endangered “Retinta Extremeña” goat for the first time to enhance its conservation interest. Genomic DNA of seventy five pureblood goats was studied. A PCR-RFLP assay was designed to find a BmyI target that distinguishing A versus B2 lineages (including recombinant variant M and B1, respectively) of the aS1-casein locus. The allelic frequency of variants related to A lineage (CAG triplet) was 14.0% similar to other southwestern Spanish breeds. It is suggested that individuals or families carrying A lineage should be more studied to detect less allergen null alleles while the opposite allele pools of the B2 lineages should be tested for alleles associated to unsaturated fatty acid content. Therefore, the priorities for conservation plans of animal genetic resources as threatened goat breeds; more investigation is claimed in the aim to study for proved useful alleles of certain genes, as casein variants.

This work is licensed under a Creative Commons Attribution 4.0 License.