FEMALE CHROMOSOMES IN COCKEREL EJACULATES

We describe a polymerase chain reaction which amplifies part of the Ec o RI repeat unit of the fowl W chromosome. The resulting 447 bp fragme nt enables DNA from female birds to be identified. The composition of this DNA is confirmed by a nested polymerase chain reaction which spec ifically amplifies a known internal 263 bp region in this fragment. Us ing this technique it is possible to follow the fate of female cells i n male germline chimaeras. The polymerase chain reaction fragment can be traced in cells of the embryonic and hatchling gonad and in adult s perm implying that cells containing the W chromosome are capable of be ing processed through the avian testis.