Navigation Links
The genetics of the white horse unraveled

The white horse is an icon for dignity which has had a huge impact on human culture across the world. An international team led by researchers at Uppsala University has now identified the mutation causing this spectacular trait and show that white horses carry an identical mutation that can be traced back to a common ancestor that lived thousands of years ago. The study is interesting for medical research since this mutation also enhance the risk for melanoma. The paper is published on July 20 on the website of Nature Genetics.

The great majority of white horses carry the dominant mutation Greying with age. A Grey horse is born coloured (black, brown or chestnut) but the greying process starts already during its first year and they are normally completely white by six to eight years of age but the skin remains pigmented. Thus, the process resembles greying in humans but the process is ultrafast in these horses. The research presented now demonstrates that all Grey horses carry exactly the same mutation which must have been inherited from a common ancestor that lived thousands of years ago.

- It is a fascinating thought that once upon a time a horse was born that turned grey and subsequently white and the people that observed it were so fascinated by its spectacular appearance that they used the horse for breeding so that the mutation could be transmitted from generation to generation, says Leif Andersson who led the study. Today about one horse in ten carries the mutation for Greying with age.

It is obvious that humans across the world have greatly valued these white horses as documented by the rich collection of stories and paintings featuring white horses. In the paper the white horse as an icon for dignity is illustrated by reproducing a painting from the late 17th century of the Swedish king Karl XI on his white horse Brilliant.

The Grey horse is also very interesting from a medical point of view since the mutation also predisposes for development of melanoma. About 75% of Grey horses older than 15 years of age have a benign form of melanoma that in some cases develops into a malignant melanoma. Thus, the study reported today has also given new insight in a molecular pathway that may lead to tumour development.

We propose that the Grey mutation stimulates growth of melanocytes and that this leads to a premature loss of the melanocyte stem cells needed for hair pigmentation whereas the mutation promotes an expansion of some of the melanocytes causing skin pigmentation, says Leif Andersson.

Domestic animals constitute extraordinary models for evolution of biological diversity as already recognized by Charles Darwin. The white horse is a beautiful illustration of the importance of regulatory mutations as a major underlying mechanism for phenotypic diversity within and between species. The Grey mutation does not change any protein structure but it affects the genetic regulation of two genes. The researchers found that the white horses carry an extra copy of a DNA segment located in one of these genes.

It is very likely that regulatory mutations like the one we found in these white horses constitute the dominating class of mutations explaining differences between breeds of domestic animals as well as between species like humans and chimpanzee, concludes Leif Andersson.


Contact: Leif Andersson
Uppsala University

Related biology news :

1. Genetics determine optimal drug dose of common anticoagulant
2. American College of Medical Genetics responds to new FDA labeling decision for warfarin
3. Rutgers Genetics receives $7.8 million for autism research
4. UD leads $5.3-million research project on rice epigenetics
5. UD leads $5.3-million research project on rice epigenetics
6. Wasp genetics study suggests altruism evolved from maternal behavior
7. Maynard Olson receives $500,000 Gruber Genetics Prize
8. UBC discovery unlocks tree genetics, gives new hope for pine beetle defense
9. Ecologists, material scientists pursue genetics of diatoms elegant, etched casing
10. Scientists achieve major genetics breakthrough
11. Environmental epigenetics has potential for preventing and treating disease
Post Your Comments:
(Date:4/3/2017)... , April 3, 2017  Data ... precision engineering platform, detected a statistically significant ... product prior to treatment and objective response ... the potential to predict whether cancer patients ... to treatment, as well as to improve ...
(Date:3/30/2017)... YORK , March 30, 2017 Trends, ... type (physiological and behavioral), by technology (fingerprint, AFIS, iris ... voice recognition, and others), by end use industry (government ... and immigration, financial and banking, and others), and by ... Europe , Asia Pacific , ...
(Date:3/27/2017)... N.Y. , March 27, 2017  Catholic ... Information and Management Systems Society (HIMSS) Analytics for ... EMR Adoption Model sm . In addition, CHS ... of U.S. hospitals using an electronic medical record ... for its high level of EMR usage in ...
Breaking Biology News(10 mins):
(Date:10/11/2017)... ... 11, 2017 , ... A new study published in Fertility ... fresh in vitro fertilization (IVF) transfer cycles. The multi-center matched cohort ... After comparing the results from the fresh and frozen transfer cohorts, the authors ...
(Date:10/10/2017)... PA (PRWEB) , ... October 10, 2017 , ... ... City Science Center’s FirstHand program has won a US2020 STEM Mentoring Award. Representatives ... the award for Excellence in Volunteer Experience from US2020. , US2020’s mission is ...
(Date:10/10/2017)... BARBARA, CALIFORNIA (PRWEB) , ... October 10, 2017 ... ... management, technological innovation and business process optimization firm for the life sciences and ... BoxWorks conference in San Francisco. , The presentation, “Automating GxP Validation ...
(Date:10/9/2017)... ... October 09, 2017 , ... At its national board meeting in North ... in Harvard University’s Departments of Physics and Astronomy, has been selected for membership in ... winning team for the 2015 Breakthrough Prize in Fundamental physics for the discovery of ...
Breaking Biology Technology: