On 24th April, Science journal published a study that presents the sequence of the bovine genome. The international research team  that carried out the study hopes their work will provide new keys to understanding the evolution of mammals, as well as providing specific new information about bovine biology.

Other possible spin-offs from this discovery include more sustainable and efficient livestock farming.

The bovine genome sequence project involved nearly 300 researchers from 25 different countries. Researchers from the Centre for Genomic Regulation (CRG) and Pompeu Fabra University played an important role in this project.

Francisco Cámara, Tyler Alioto and Roderic Guigó, from CRG, contributed to the identification of the genes on the bovine genome, while Roderic Guigó led the international team that carried out the experimental verification.

Mireya Plass and Eduardo Eyras, from the Research Group on Biomedical Informatics, studied the conservation of the genes' structure between the bovine genome and the human, mouse and dog genomes. Eduardo Eyras led the international team that carried out the verification of this comparative genomics study.

The project lasted six years. During this time, a genome from a specimen of the Hereford cow (Bos Taurus) called L1 Dominette w as sequenced and analyzed. The Hereford breed comes from England. It is one of the most important meat-producing breeds and is characterized by its lack of horns. Until now, the mammals which had been sequenced were laboratory animals and human beings. The sequencing of the cow's genome represents the first sequencing of an animal of interest for stockbreeding.

The next goal will be to explore the sequence of the bovine genome more deeply in order to understand the genetic basis of the ruminants' evolutionary success and have the opportunity to solve some of the current crucial issues, such as sustainable and efficient food production for a growing population, as pointed out by Dr. Richard Gibbs, director of the BCM Human Genome Sequencing Center and the project's main researcher.

Keys to understand the evolution of mammals and the improvement of livestock farming

Researchers have observed that the Bovine Genome, formed by more than 22,000 genes, is more similar to the human than the mouse or rat genome and that most livestock chromosomes correspond, partially or totally, to human ones, although the DNA location varies in some areas.

The study shows that the human and cow genomes share, especially, the organisation of their chromosome architecture. That is what makes them closer to each other and distances the human from the mouse genome. There appear to be a large number of duplicated segments

and other changes in the layout of the chromosomes.

Some of these changes seem to be important for livestock biology in so far as they affect the genes involved in the immune system, lactation, metabolism and digestion. These changes may explain the livestock's exceptional ability to efficiently turn low-quality forage into high-energy meat and milk.

For example, one of these variations affects the histatin gene in the mammary tissue, which undergoes a special regulation during lactation, producing a new protein in milk which has anti-microbial properties. This gives protection to the calf but also to the cow in facing possible infections in a very exposed tissue.

Another change happens with immunoglobulin G passing into the milk. This protein, present in milk, gives immunity to calves suckling from their mothers.

Researchers state that the study "makes the identification of new functions and regulation systems of great importance to mammals easier". The bovine genome project gives us some keys to understanding the evolution of livestock and favours the improvement of livestock farming.

With eight research groups on Computational Genomics, the Barcelona Biomedical Research Park (PRBB), which includes the GRIB (UPF-IMIM) and the CRG, a centre attached to the UPF, is in an exceptional position in Europe with regard to this important scientific discipline. In this context, the presentation of the genomic sequencing platform in Barcelona must put our country among the leading countries in regard to genomics, one of the key scientific-technological disciplines of the 21 ^st century.

Reference Works: The Bovine Genome Sequencing and Analysis Consortium, Christine G. Elsik, Ross L. Tellam, Kim Worley. "The Genome Sequence of Taurine Cattle: A Window to Rumiant Biology and Evolution". Science, vol. 324, doi:10.1126/science.1169588 (2009).