Differentiation of Restriction Sites in Ribosomal DNA in the Genus Gallus

Abstract

We studied the genetic relationships of four species of jungle fowl and the domestic fowl by the differentiation of the restriction sites in ribosomal DNA (rDNA). Almost no polymorphisms were observed, however, there were polymorphisms seen in Sac I and Pst I sites after hybridization with the 18S probe. Although a 2.7kb Sac I site was missing in the red jungle fowl and in most domestic fowl, it existed in the other three species of jungle fowl and in one line of domestic fowl. In addition, a Pst I site in the vicinity of 2.3kb was not observed in any of the jungle fowl species other than the Ceylon jungle fowl. Another Pst I site in the vicinity of 1.8kb, hybridized with the INT probe in the green jungle fowl was observed, these two bands seem to be unique to each of these species. Since most of the domestic fowl lacked the Sac I site, it is thought that the red jungle fowl, which likewise lacks the site, played a major role in the formation of the domestic fowl. However, there was one strain of domestic fowl that shared this Sac I site with the gray jungle fowl, the Ceylon jungle fowl and the green jungle fowl except the red jungle fowl, suggesting the possible involvement of jungle fowl species in the formation of the domestic fowl.