An important phase of an international project to map the sheep genome has taken a big step forward, Meat & Wool New Zealand, AgResearch and Ovita have announced.

Following completion of the sequencing of the sheep genome to three-fold coverage, the first assembly of a draft sequence of the sheep genome has now been achieved. When fully completed, the entire project will provide significant benefits for both farmers and human health researchers.

Meat & Wool New Zealand research and development Manager Max Kennedy says the initial assembly of the interim low coverage sequence of the sheep genome is one step towards identifying DNA variants and also allows scientists to use the sheep genome sequence directly for the first time.

“This will enable researchers to accurately position DNA variants on the genome. The identification of these variants is the primary goal of the next phase of the project.”

When the project is complete, it will allow the development of tools to help farmers identify genes associated with important production, quality and disease traits in sheep, he says.

AgResearch Senior Scientist, John McEwan said the project has generated more than 9.7 billion bases (9.7 Giga bases) of sequence from six sheep. While modest by world standards, this is by far the largest sequence assembly project attempted in Australia and New Zealand.

The assembly has been created by New Zealand and Australian researchers who are part of the International Sheep Genomics Consortium (ISGC). The ISGC is a collaboration between scientists (and their organisations) from 16 countries including Australia, New Zealand, the United States, and United Kingdom that contributed to the current work. The purpose of the Consortium is to develop genomic resources in the public domain. 

The skim sequencing of the genome has been completed in only seven months and utilised the latest “next generation” sequencing methods. It was conducted simultaneously at Otago University in Dunedin and at the Human Genome Sequencing Centre at the Baylor College of Medicine, Houston, Texas.

In the current project AgResearch staff have been involved in sequencing strategy simulations, have undertaken a major part of the sequencing using the Otago facility, have developed a database to store all the sequences collected and are undertaking sequence assembly and subsequent SNP detection in conjunction with Australian researchers.

The New Zealand work is part of Meat & Wool New Zealand and AgResearch’s Ovita Investment. The sequencing by Baylor and the Australian contribution to the assembly were financed by CSIRO, an Australian Government International Science Linkages Grant, Sheep Genomics (Meat and Livestock Australia and Australian Wool Innovation Ltd) and the University of Sydney with additional support for sequencing by Genesis Faraday from the United Kingdom.

The sequence will be used by all sheep researchers. As the sheep is used widely as a human medical model for a number of diseases such as osteoporosis, the flow-on effects of this research should have considerable benefits in the area of human health as well.