Estudo do polimorfismo genético da alfa-S1-caseína : um paradigma para melhorar a qualidade e o uso do leite de cabra na alimentação humana

Abstract

In the Northeast of Brazil, in the semi-arid region,exists a breeding vocation area of cattle, especially exploring domestic ruminants including caprines. In the last decades the milk of goats has been indicated as a protein source to the diet of children with allergic reactions to the bovine milk. Among the proteins known casein, alpha-S1-casein was the first truly proved on basis of the genetic polymorphism. Aiming characterizes the herds of milk goats of the backcountry, rural and forest zone from Pernambuco State, the PCR-RFLP technique was used and it was studied the polymorphism of the gene of a-s1-casein. Using 60 goats of the breeds Moxotó, Alpine American and halfbreed, the DNA was extracted by chloroform and phenol protocol and the gene of the a-s1-casein was amplified by PCR's technique. Followed it the restriction enzyme Xmn I was used to obtain the frequency allelic of the studied breeds. It was verified the presence of the gene type D, for the American Alpine animals and the gene type B/D for the Moxotó and half-breed breeds. It was concluded that there are genetics variations for the a-s1-casein from the milk of the caprice breeds in the region.