The identification of broad classes of DNA probes which detect hypervariable genetic markers in different taxa is invaluable for parentage analysis in wild vertebrates. Restriction-fragment-length polymorphisms, detected by hybridization of a mouse class II major histocompatibility complex (MHC) cDNA probe to genomic DNA from red-winged blackbirds (Ageluius phoeniceus), are shown to have the genetic characteristics of a single hypervariable locus with many codominant alleles. Surveys of DNA from unrelated individuals that was cut with a single restriction enzyme (EcoRI) revealed a large number (37) of resolvable alleles with a low mean frequency (P = 0.02 I ). When RFLP data from multiple enzymes are combined with segregation data, individual-specific haplotypes can be generated. These characteristics make this probe ideal for parentage analysis in this and other blackbird species. The many MHC probes available from mice and humans may provide a valuable source of hypervariable single-locus genetic markers, precluding the necessity of isolating species-specific probes from genomic libraries
To investigate the genetic characteristics of RFLPs detected by the mouse MHC probe, blood samples were collected from individually color-banded adult and nestling red-winged blackbirds from a population located near the Queen’s University Biological Station, Chaffey’s Lock, Ontario, in 1986. Adults were lured into mist nets, and then samples (50-200 ~1) of whole blood were collected from the jugular vein, added to Vacutainers, and stored at -20°C until DNA extraction. Blood samples were also collected from 6-d-old chicks taken from nests tended by individually marked adults. Assignments of particular adult males and females as the putative parents of families of chicks were based on the behavioral association of the adults with a particular nest. In the present paper we analyze samples collected from 92 nestlings from 29 families and from 77 putatively unrelated adults.