Development and validation of RP-HPLC method for the quantitative estimation of as1-genetic variants in goat milk.

A high-performance liquid chromatographic (HPLC) method was developed and validated for separationand quantification of the most common genetic variants of as1-casein in goat’s milk, to evaluate the effectof as1-casein polymorphisms on casein content.Chromatography was carried out by binary gradient technique on a reversed-phase C8 Zorbax columnand the detection was made at a wavelength of 214 nm. The procedure was developed using individualraw milk samples of Girgentana goats. For calibration experiments, pure genetic variants were extractedfrom individual milk samples of animals with known genotypes, considering that commercial standardsfor goat genetic variants were not available. The data obtained for Girgentana goat breed showed that A,B, F variants were alleles associated with a content of as1-casein in milk of 3.2 ± 0.4, 5.4 ± 0.5 and0.7 ± 0.1 g/L, respectively, whereas N variant was a ‘null’ allele associated with the absence of as1-caseinin milk.