Sequence analysis of a zinc-finger gene for the examination of paternal lineages and introgressive hybridization in North American deer

Abstract

By direct sequence analysis of the mammalian zinc-finger Y (Zfy) gene, interspecific and intraspecific variations were documented in a Y-chromosomal locus in North American deer. The evolutionary history of paternal lineages was distinctly different from maternally inherited mitochondrial DNA (mtDNA). It was hypothesized that introgressive hybridization resulted in the introduction of mtDNA from white-tailed deer (Odocoileus virginianus) into the mule deer (O. hemionus) population, but this introgression did not involve the nuclear Ychromosomes. Sequence divergences of Zfy for white-tailed deer, mule deer, and black-tailed deer (also 0. hemionus ) were consistent with traditional taxonomy with black-tailed and mule deer being more closely related to each other than either is to white-tailed deer. Conversely, mule deer and white-tailed deer share mtDNA haplotypes that are quite distinct from that of black-tailed deer. Sequence data (Zfy) were used to determine a diagnostic restriction site which could distinguish between the Y-chromosomes of white-tailed deer and mule deer. The restriction enzyme MseI created restriction fragment length polymorphisms (RFLP) which were assayed to determine-nine paternal origin. Two individuals from within the Trans-Pecos contact zone were diagnosed as hybrids. Additionally, an offspring derived from the controlled mating of a female mule deer and a male white-tailed deer possessed the white-tailed deer RFLP pattern as expected.