Milk Matters: Bovine genome provides tools for unraveling the secret of milk’s nutrition

Joseph O’Donnell

Joseph O’Donnell

By Joseph O’Donnell


When did you first hear the term, deoxyribonucleic acid or DNA? I don’t remember hearing the phrase until I was well into my college years, and I majored in Biochemistry! Scientists James Watson and Francis Crick defined the structure of DNA in 1953, and went on to win the Nobel Prize in 1962. James Watson (American) reputedly boasted, “We have found the secret of life.” More than a half a century later we are still grappling with this “secret” and how we can use it to improve human health.  


What’s the genome?

Today, we do know that DNA is organized into units called genes. When you put all the genes from one living thing together you get what’s called the genome of that plant or animal or bacteria.

Trying to figure out the “secrets” hiding in these genomes is not for the faint of heart. Since DNA was discovered an entire field of science developed – with corresponding fancy equipment and specialized skills. What used to take painstaking weeks or months experimenting in test tubes today is done in a matter of hours automatically by a machine that never stops. It’s reached the point where big genomes like mammals can be chemically defined or “sequenced” in a few years rather than a few decades. 


A puzzle in a box

Once genomes are sequenced it’s like having a big jigsaw puzzle in a box. From there you have to sort out the pieces to understand what each represents; and there are billions of them. For example, will you have blue eyes or brown eyes? Will you be tall or short? Have curly hair or straight? All the genetic information that makes you you is in that box waiting for scientists to make sense of it. The race is on and the priorities will likely relate to health, one of our most pressing issues.

The release of the human genome in 2003 opened a new area of discovery and the field exploded with scientists throughout the world eager to apply this knowledge to other species – including the bovine. After all, human civilization is closely linked to the humble cow. It is used around the world to supply draft labor, meat and milk and has been an essential part of our survival since we first domesticated cattle more than 9000 years ago.  


Bovine follows human mapping

The same year the human genome was unveiled, a global effort involving 300 scientists around the world and more than $50 million was launched to map the bovine. This important project, however, was lacking in one fundamental area – looking closely at bovine lactation genes. It took the support of California dairy producers and an alert scientific community (primarily at UC Davis) to generate information essential to the heart of the dairy industry – what genes are responsible for the nutritional package that is milk? 

The Bovine Genome work was published in the highly regarded journal, Science in April. On the same day, a related paper addressing the lactation component of the bovine genome was published in the online journal, Genome Biology. Since then, the coverage has been terrific – and no wonder.


Getting to the good stuff

With the individual puzzle pieces of the cow in our box, we can now get to the good stuff. With these basics in place, scientists around the world can and will accelerate their work on animal health, muscle development, milk production (quantity and composition), reproduction, efficiency of conversion of forage to milk and meat, reduction of greenhouse gas production – the list is infinite. 

The real bottom line in all of this is creating a healthier world as the products from our cows deliver unmatched nutrition to a global population. U.S. dairy cows will become more efficient, more sustainable, more environmentally friendly and healthier and the products, especially milk, they produce will be tailored to deliver specific benefits to human consumers. All food producers use breeding techniques to try to build health advantages to the humans who consume their products. 


Milk’s distinct advantage

Milk enjoys the distinct advantage of an ancient association with humans and a common physiological process, lactation. Sorting out the means to convert bovine milk to be more human-like is not insurmountable. This strategy will occupy scientists’ attention for many years to come. All the while consumers will realize the increased value of milk.

Much of this information can be found on the International Milk Genomics Consortium (IMGC) Web Portal: This site contains the references to all the papers listed above as well as deep insights into where this field is taking us as an industry and as consumers. 


All dairy benefits

All dairy products can benefit from milk genomics. Whether it is making tastier cheese or delivering health benefits such as satiety, relief from gastrointestinal distress, improved immune responses or more – the world will continue to become a better and healthier place through the partnership of humans and bovines.



  Dr. Joseph O’Donnell is executive director of the California Dairy Research Foundation. He can be reached at 530-753-0681. Information on the California Dairy Research Foundation can be obtained from the organization’s web site at