Gene frequencies of caprine αs1-casein polymorphism in Spanish goat breeds

Abstract

Using electrophoretic techniques (PAGE-SDS and IEF), we report allelic frequencies of caprine α s1-casein (Cn) locus in four Spanish milking breeds: Murciana-Granadina, Malagueña, Payoya and Canaria. The E allele (intermediate content of α s1-Cn in milk) was predominant in dairy breeds Murciana-Granadina , E:0.59; Malagueña, E:0.65 and Payoya, E:0.76, while alleles A and B (high content of α s1-Cn) were more frequent in the Canaria dairy breed (A:0.28 and B:0.32). Among the Spanish breeds, Canaria represents a particular case where 60% of the alleles were of the high type (A and B). The ethnical group Canaria Palmera was particularly high in the frequency of alleles A and B (91%) very similar to the Italian Garganica breed (98%). The low frequency of F allele (reduced level of α s1-Cn) in Spanish breeds ( Murciana-Granadina, F:0.08; Malagueña, F:0.04; Payoya, F:0.00 and Canaria, F: and Saanen breeds. It is important to note that in the Payoya breed no low or null alleles (F, D, 0) were detected. It seems unlikely that genetic selection for milk production has had a significant influence in determining the α s1-Cn allelic distribution in goat populations. The direct relationship existing between these allelic variants and differences in the Cn content and in the physico-chemical properties of milk, can be used as a tool in the improvement of milk processing quality and cheese yields of Spanish milking breeds.