|M.Sc Student||Eitan Yuval|
|Subject||Development of Methods for Analysis of Genomic Polymorphism,|
and Their Application to Domestic Chickens
|Department||Department of Biotechnology and Food Engineering||Supervisor||Professor Yechezkel Kashi|
The study presented here concerns with genomic diversity, with the domestic chicken genome as a model. Three chicken breeds, that exhibit different key traits, were chosen for this study: White-Rock broilers, Leghorn layers and local desert chickens. In order to examine genomic variation, four genes were chosen for this study: hsp70, hsp90, hsp108 and myostatin. The first aim of this study was to evaluate the extent and architecture of genomic diversity within and between the desert and White-Rock chicken breeds, in the four genes. The second aim was to develop efficient simple methods for following such genomic polymorphism, and to apply them to the chicken model. The DNA nucleotide sequence of sixteen segments within the four genes was determined by cycle sequencing and automated analysis, for five desert and five White-Rock chickens. Within the total of about 7850 sequenced bases, 76 polymorphic points were found, most of which were single nucleotide polymorphisms.
As part of the research, two novel methods were developed: one for tracking mono-nucleotide repeat alleles, and another for direct simple identification of multiple-point micro-haplotypes.
We found that sufficient genomic diversity can be found within the commercial breeds, despite the continuous selection they have been undergoing. This diversity is crucial as the basis for marker assisted selection, as this may become the next step in genetic improvement of breeds. Unsurprisingly, the desert chicken breed, which was not submitted to such selection, was found to be more diverse. The methods developed in this work enabled us to examine numerous individuals rather simply, and learn their genomic architecture.
For this study chickens served as the genomic model, but the methods we developed and implemented are readily suitable for implementation in any other diploid organism, including human.