Expressed sequence tags for the chicken genome from a normalized, ten-day-old white leghorn whole embryo cDNA library. 2. Comparative DNA sequence analysis of guinea fowl, quail, and turkey genomes

Accelerated efforts to develop a high-utility chicken genome map have resul ted in the development of resources that may be useful for genetic analysis in other economically important poultry species. Here we describe a total of 26 comparative genomic DNA sequences (CGS) for the guinea fowl, Japanese quail, and domestic turkey developed using 10 primer pairs specific for 10 previously reported, unique, chicken expressed sequence tags (EST). The to tal length of CGS developed for each of the three species was 4,193, 4,597, and 6,057 bp in quail, turkey, and guinea fowl, respectively. About 70% of the CGS showed significant sequence similarity to reference database seque nces, including the reference chicken EST and other avian and nonavian gene s. A majority of the between-species comparisons of the CGS from all but tw o primer pairs were significant and ranged from 81 to 99%. The percentage s imilarity of the CGS appears to be a function of phylogenetic relatedness a nd was generally higher for comparisons between the chicken, quail, and tur key and lower between the guinea fowl and chicken, quail, or turkey. Maximu m likelihood estimation of the phylogenetic relationships using CGS from tw o primer pairs also showed a closer relationship, as expected, among chicke n, quail, and turkey than between guinea fowl and either chicken, quail, or turkey. Within the guinea fowl, quail, and turkey CGS developed, the total number of single nucleotide polymorphisms detected was 28, 17, and 14, res pectively. Together, these resources represent tools that will facilitate g enetic analysis of species that have been studied very little and our under standing of their genomes and genome evolution.