Featured Research

from universities, journals, and other organizations

Nine genes account for pigmentation in the fruit fly

Date:
June 11, 2013
Source:
Veterinärmedizinische Universität Wien
Summary:
Individuals of a particular species generally differ from one another. We are clearly most adept at recognizing members of our own species, although dog and cat owners will be ready to confirm that their pets look unique. Differences within species relate to characteristics such as size and shape but also to color: it is not only humans that show a wide range of skin pigmentation. Nevertheless, the cause of the variation in skin color in animals has remained largely a matter for conjecture. Recent work sheds light on the topic.

Individuals of a particular species generally differ from one another. We are clearly most adept at recognizing members of our own species, although dog and cat owners will be ready to confirm that their pets look unique. Differences within species relate to characteristics such as size and shape but also to colour: it is not only humans that show a wide range of skin pigmentation. Nevertheless, the cause of the variation in skin colour in animals has remained largely a matter for conjecture. Recent work in the group of Christian Schlötterer at the University of Veterinary Medicine, Vienna sheds light on the topic.

The results are published in the online journal PLOS Genetics and point to a general method for studying variation in natural populations.

The skin colour of humans ranges from pale pinkish-white to very dark brown and relates largely to the amount of melanin produced by specialized cells in the body. The synthesis of melanin is under the influence of a bewildering array of genes, each of which naturally occurs in a variety of different forms or alleles, thus accounting for the wide variety of skin colours found in our species. But how precisely the variation is brought about is still unknown.

Nine genes account for pigmentation in the fruit fly

Colour also differs, albeit sometimes more subtly, in many other animals. For example, the colour of the abdomen in the fruit fly Drosophila melanogaster varies substantially. Because flies are much more amenable to genetic study than humans, we know a good deal about pigmentation in this species. At least nine genes are directly involved in the synthesis of pigment, together with a number of others that indirectly affect the pattern of pigmentation. Nevertheless, it is not clear whether changes in these genes account for the variation in the pigmentation of natural populations of flies or whether differences in other genes might somehow be responsible.

DNA sequence comparison elucidates genetic variation

The issue has been tackled by Héloïse Bastide and Andrea Betancourt at the Institute of Population Genetics of the University of Veterinary Medicine, Vienna (Vetmeduni Vienna). The researchers examined 8,000 female flies, split into 5 groups, and chose 100 of the lightest and 100 of the darkest from each group for genetic comparison. Each group of light and dark flies was pooled and its DNA sequenced, resulting in a catalogue of the genetic differences between light and dark flies at over three million positions in the fly genome. Sophisticated statistical methods were used to compare the differences between the two groups, leading to the discovery of 17 sites where variation, so-called single-nucleotide polymorphisms or SNPs (pronounced "snips"), seemed to be associated with the extent of female abdominal pigmentation.

Effective method to study natural variation

Gratifyingly, the SNPs were found to lie in or close to genes known to be involved in pigment synthesis, in particular the tan and bric-à-brac1 genes. Most of the SNPs were not in the coding sequence of these genes but instead in nearby sequences that had previously been shown to regulate their activity. In other words, the variation in the colour of female flies is not a result of changes to the genes that produce pigments but stems instead from subtle alterations in the regulation of the pigmentation genes. Bastide and Betancourt are naturally excited by their findings. As they say, "Our work has taught us a lot about how pigment production can be controlled and at least some of our conclusions may apply to other species as well. But even more importantly, our experiments show that pooling and sequencing samples can represent an effective and low-cost method to examine the basis of natural variation in populations."


Story Source:

The above story is based on materials provided by Veterinärmedizinische Universität Wien. Note: Materials may be edited for content and length.


Journal Reference:

  1. Héloïse Bastide, Andrea Betancourt, Viola Nolte, Raymond Tobler, Petra Stöbe, Andreas Futschik, Christian Schlötterer. A Genome-Wide, Fine-Scale Map of Natural Pigmentation Variation in Drosophila melanogaster. PLoS Genetics, 2013; 9 (6): e1003534 DOI: 10.1371/journal.pgen.1003534

Cite This Page:

Veterinärmedizinische Universität Wien. "Nine genes account for pigmentation in the fruit fly." ScienceDaily. ScienceDaily, 11 June 2013. <www.sciencedaily.com/releases/2013/06/130611084059.htm>.
Veterinärmedizinische Universität Wien. (2013, June 11). Nine genes account for pigmentation in the fruit fly. ScienceDaily. Retrieved September 30, 2014 from www.sciencedaily.com/releases/2013/06/130611084059.htm
Veterinärmedizinische Universität Wien. "Nine genes account for pigmentation in the fruit fly." ScienceDaily. www.sciencedaily.com/releases/2013/06/130611084059.htm (accessed September 30, 2014).

Share This



More Plants & Animals News

Tuesday, September 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Earth Has Lost Half Its Vertebrate Wildlife Since 1970: WWF

Earth Has Lost Half Its Vertebrate Wildlife Since 1970: WWF

Newsy (Sep. 30, 2014) — A new study published by the World Wide Fund for Nature found that more than half of the world's wildlife population has declined since 1970. Video provided by Newsy
Powered by NewsLook.com
California University Designs Sustainable Winery

California University Designs Sustainable Winery

Reuters - US Online Video (Sep. 27, 2014) — Amid California's worst drought in decades, scientists at UC Davis design a sustainable winery that includes a water recycling system. Vanessa Johnston reports. Video provided by Reuters
Powered by NewsLook.com
Argentina Worries Over Decline of Soybean Prices

Argentina Worries Over Decline of Soybean Prices

AFP (Sep. 27, 2014) — The drop in price of soy on the international market is a cause for concern in Argentina, as soybean exports are a major source of income for Latin America's third largest economy. Duration: 01:10 Video provided by AFP
Powered by NewsLook.com
Mama Bear, Cubs Hang out in California Backyard

Mama Bear, Cubs Hang out in California Backyard

Reuters - US Online Video (Sep. 27, 2014) — A mama bear and her two cubs climb trees, wrestle and take naps in the backyard of a Monrovia, California home. Vanessa Johnston reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins