Navigation Links
Unscrambling the genetics of the chicken's 'blue' egg

They are the latest foodie fashion and look set to become big business in the baking aisles of all the major supermarkets the blue egg produced by some chickens is prettier and some say tastier and cleaner-breaking than the traditional brown one and now, thanks to scientists from The University of Nottingham, we know what caused the eggs in some breeds to turn this unusual colour.

In a four-year research project just published in the journal, PLOS ONE, the team from the School of Biology, has identified the genetic mutation which first produced the blue egg in native South American chicken, the Mapuche fowl, and their European descendants, Araucana between 200 and 500 years ago. The results could inform future research into agricultural breeding techniques if demand for the blue egg continues to grow.

The scientists used the unique genetic resources conserved by heritage or 'fancy' poultry breeders to identify at fine resolution the exact location of the mutation in the genome in blue egg laying chicken. This work was followed by further genomic study which revealed the genetic cause of the blue coloured egg shell surprisingly an ancient harmless retrovirus in the domestic chicken.

A retrovirus is a virus that, unlike most cellular organisms, carries its genetic blueprint in the form of ribonucleic acid (RNA). It reproduces itself in a host cell using a special enzyme called 'reverse transcriptase' which transcribes RNA into deoxyribonucleic acid (DNA). This makes it possible for genetic material from a retrovirus to become permanently incorporated into the DNA of an infected cell. In this case, the retrovirus' effect was to trigger an accumulation of a green-blue bile pigment called biliverdin in the eggshell as the egg develops in the hen.

Leading the team, BBSRC doctoral research fellow, David Wragg said: "An unexpected find was the unique integration sites for the retrovirus in South American/European and Asian chickens. It shows the importance of viruses in shaping evolution and diversity of species. It's quite remarkable retroviruses are generally considered to integrate at random locations in the genome, and so the chance of a retrovirus integrating at more or less the same location in two chicken populations is extremely low. Moreover, when appearing in the population, the unusual egg coloration must have attracted the attention of the owners, who must be praised for having selected the trait in subsequent breeding."

Co-researcher, Dr Joram Mwacharo added: "Of course it's not only some breeds of chicken that produce blue eggs. They are commonly found across species of birds including those that lay blue eggs as well as non-blue eggs within a single population, like the cuckoo and guillemot. It's therefore entirely possible that retroviruses could be playing a part in the diversity of egg colour and patterning across avian species more generally, but this remains to be studied."

The work was initiated by Professor Olivier Hanotte whose curiosity about blue eggs was sparked on a trip to Brazil where he met Professor Jos Antonio Alcalde, co-author of the paper. He said: "This is an important discovery because some of these rarer native breeds of chicken with this unusual egg colour and high quality have become low in number and are in danger of disappearing if not conserved and indeed promoted by agriculture."

Significantly, the same findings have also been independently discovered and reported this year by a research group in China which has examined local Chinese and North American breeds.


Contact: Emma Rayner
University of Nottingham

Related biology news :

1. Epigenetics and epidemiology -- hip, hype and science
2. Genzyme/ACMG Foundation Genetics Training Award in Clinical Biochemical Genetics announced
3. Not by DNA alone: How the epigenetics revolution is fostering new medicines
4. Study finds voter genetics may predict election outcomes
5. The Genetics Society of America announces DeLill Nasser Travel Award recipients
6. MARC travel award announced for the 2012 GSA Yeast Genetics and Molecular Biology Meeting
7. $500,000 Gruber Foundation Genetics Prize goes to Philadelphia scientist
8. Dr. Douglas Wallace to receive Gruber Foundation 2012 Genetics Prize
9. Genetics Society of Americas Genetics journal highlights for July 2012
10. New study announced that will use genetics to test for Alzheimers risk
11. Sick from stress? Blame your mom… and epigenetics
Post Your Comments:
(Date:11/18/2015)... --> --> ... report titled  Gesture Recognition Market - Global Industry Analysis, ... to the report, the global gesture recognition market was valued at ... US$29.1 bn by 2021, at a CAGR of 20.3% ... dominated the global gesture recognition market in ...
(Date:11/17/2015)...  Vigilant Solutions announces today that Mr. Dick ... --> --> Mr. ... partnership at TPG Capital, one of the largest global ... in revenue.  He founded and led TPG,s Operating Group, ... from 1997 to 2013.  In his first role, he ...
(Date:11/12/2015)... Nov. 12, 2015  A golden retriever that stayed ... dystrophy (DMD) has provided a new lead for treating ... the Broad Institute of MIT and Harvard and the ... . Cell, pinpoints a protective ... the disease,s effects. The Boston Children,s lab of ...
Breaking Biology News(10 mins):
(Date:11/30/2015)... 2015  Northwest Biotherapeutics (NASDAQ: NWBO ) ("NW ... therapies for solid tumor cancers, announced today that the ... and the Company welcomes Neil Woodford,s call ... anonymous internet report on NW Bio.  The Company,s Board ... Powers stated, "We agree with Mr. Woodford that, ...
(Date:11/30/2015)... PETACH TIKVAH, Israel , Nov. 30, 2015 ... ), a leading developer of adult stem cell technologies for ... Therapeutics Ltd., has been awarded an additional grant of approximately ... Chief Scientist (OCS). This grant, the second this year, brings ... to approximately $1.8 million (approximately NIS7 million).  ...
(Date:11/27/2015)... Nov. 27, 2015 /PRNewswire/--  Mallinckrodt plc (NYSE: ... that it has closed the sale of its global ... (GBT- NYSE Euronext) in a transaction valued at approximately ... facilities and a total of approximately 1,000 employees spread ... St. Louis area. This entire workforce ...
(Date:11/27/2015)... , November 27, 2015 ... Growing popularity of companion diagnostics is ... cancer biomarkers market with pharmaceutical companies and ... companion diagnostic tests. . ... Complete report on global cancer biomarkers ...
Breaking Biology Technology: