TRIPLICATED ALPHA-GLOBIN LOCI IN MANCHEGA SHEEP

The RFLP (restriction fragment length polymorphism) technique was used to study the ac-globin locus in two breeds of Spanish dairy sheep: Ch urra and Manchega. Churra and sixteen Manchega sheep had normal chromo somes, that is, with two copies of the a-globin genes (alpha alpha/alp ha alpha). However, seven Manchega sheep had heterozygous chromosomes with three alpha-globin loci (alpha alpha/alpha alpha alpha). The orig in of chromosomes with triple loci can be explained by unequal crossov ers between two normal chromosomes. (C) 1998 Elsevier Science B.V.