IMPLEMENTATION OF WHOLE GENOME SELECTION IN NORTH AMERICAN JERSEY CATTLE
Animal Genomics and Improvement Laboratory
2013 Annual Report
1a.Objectives (from AD-416):
ARS and the Cooperator are interested in investigating the commercial application of whole genome selection in Jersey cattle. This investigation is essential for gauging if genome enhanced predictions of genetic merit are as or more reliable than current statistical-based methods of estimating genetic merit; ultimately allowing the Cooperator to accelerate selection for genetic improvement and intensify outputs in current production scenarios. Our Project Plan has two objectives:.
1)collect DNA samples and generate ~50,000 SNP marker genotypes from each of more than 700 elite animals in the Jersey herdbook; and.
2)analyze this data through the whole genome selection analysis pipeline to generate genome enhanced predictions of genetic merit. The Cooperator has the funding and access to important animals of the breed through its membership and partnership with members of the National Association of Animal Breeders. ARS has the expertise and facilities to process these samples across the BovineSNP50 genotyping assay and generate SNP marker genotypes for analysis of whole genome selection.
1b.Approach (from AD-416):
The project will be managed jointly between ARS and the Cooperator. The Cooperator will evaluate its animal registry and lead collection of DNA from appropriate animals for genotyping. ARS will generate and analyze the SNP marker genotypes using BovineSNP50 data. These resources will provide the data needed to generate genome enhanced predictions of genetic merit for the Jersey breed; thus aiding selection of superior animals by the Coopeerator for its member and partners practicing selection for genetic improvement. ARS will analyze, store, and distribute genotypic information (as agreed upon with the Cooperator) that will be used for whole genome selection studies. Both ARS and the Cooperator will jointly work together to collect and curate DNA samples. Also, as needed, both parties will educate breeders and members in the process of whole genome selection.
All of these activities will be considered true collaborations and thus, by definition, each party will be considered to have provided a true intellectual contribution consistent with authorship.
ARS scientists met planned objectives, and Jersey cattle are now a part of the “official” genetic evaluations based on genetic predictions using genome-wide marker data. ARS scientists extended analysis of this data to identify a small genomic region of chromosome 15 (called JH1 for Jersey haplotype.
1)that causes early embryonic loss when two copies (homozygous) are inherited from the parents (one copy from each parent). The details of the work on JH1 were reported in a manuscript. ARS scientists continue to work on identifying the causative mutations underlying other genetic defects in Jersey cattle including rectovaginal constriction and limber leg defects. Both traits are now mapped to small specific regions of the genome, and this information can be used by breeders to improve selection. Additional work is being done to characterize the genetic differences between animals from North America and the Isle of Jersey to better understand how artificial selection has modified the genome between these two isolated lines of cattle. This information will help to guide bioconservation of rare germplasm and future selection of Jersey cattle for improved production. This research supported two objectives of the in-house project to enhance genetic improvement of food animals across a spectrum of ruminant production systems and characterize functional genetic variation for improved fertility and environmental sustainability of ruminants.