14TSB_ATC_IR Genome biobanking for the optimisation of valuable broiler genetic stocks

点击翻译按钮获取中文摘要

This project will develop novel technology to safeguard and harness existing poultry genetic resources by i) biobanking genetic resources for broiler lines using PGCs (the chicken functional equivalent of the mammalian stem cell) to preserve genotypes and therefore have the potential to re-introduce genotypes as needed into poultry production systems. Recent developments using PGCs provide a business opportunity to exploit a novel technology to safeguard and manage unique genetic pedigree breeding flocks. Currently there is no way to reconstitute pedigree stocks if lost to disease or natural disaster. Valuable lines that could contain useful alleles for developing markets are either maintained as living flocks or are culled from the production process. A proven biobanking procedure, coupled with complete genotyping of the biobanked material, will permit the storage of PGCs which can be returned to production as needed. Unlike mammalian agricultural species, the broiler industry is hindered by the limited semen cryopreservation program and semen storage technologies that are only reliable for hours, not days, months, or years. The use of chicken PGCs (stem cells) as a cryopreservation system has recently developed (van de Lavoir, 2006) and has not yet been developed by any of the large commercial poultry breeders. We intend to preserve the Vantress heritage line of chickens, a/the founder line for the current Cobb pedigree broiler lines that we have kept extant for the last fifty years. It thus represents an ancestral pool of genes from which the genomes of the modern lines have been selected. It will therefore include potentially useful alleles that have already been lost from the modern lines, or may be lost in the future with further selection. Cryopreserving genetic material is only one part of an integrated program to access and preserve genetic diversity required for the development of new products for emerging and transforming market segments. A careful assessment of the available genetic variation, along with an understanding of which alleles are critical for driving key performance traits is necessary to exploit the existing genetic diversity in commercial and non-commercial genetic stocks. Recent advances in sequencing technologies and efforts have provided a valuable assembly of a reference chicken genome. As the product of a publically and privately funded consortium, the effort focused on the ancestor of the modern chicken, the red jungle fowl. However, to effectively utilize genomic selection strategies in the commercial industry, a comprehensive understanding of the alleles and associated phenotypic traits of commercial purelines must be completed. To this end, this project will undertake ii) further DNA sequencing and annotation of the genomic sequence of a broiler line to produce a GeneAtlas; model for better understanding genetic variation in modern broiler lines. Currently, our ability to understand variability within and between lines of chickens is hampered by the incomplete state of the current chicken genome build and the distant relationship between modern broiler lines and the red jungle fowl. A broiler GeneAtlas will allow the exploitation of broiler genetic variability for the introgression of biobanked genetic material into new pureline populations. This broiler Atlas will be specific for Cobb commercial purelines and ancestral Cobb broiler lines. This will be a unique resource that will enable Cobb to select traits from within their various production flocks for specific markets.