Navigation Links
Breeding success by delving into the honey bee sex gene

A research team led by University of Michigan evolutionary biologist Jianzhi "George" Zhang, has uncovered evolutionary //facts about a gene called csd, which is a sex determiner in honey bees. These novel inputs can indeed be ploughed back into formulation of improved methods to breed honeybees, who are effective pollinators of crops that are valuable to the economy. The findings of Zhang and collaborators are published in a special issue of Genome Research exclusively dedicated to the biology of the honey bee. The issue will be available online and in print Oct. 26.

Scientists have long known that in bees—as well as wasps, ants, ticks, mites and some 20 percent of all animals—unfertilized eggs develop into males, while females typically result from fertilized eggs. But that's not the whole story, and the discovery in 2003 of csd (the complementary sex determination gene) helped fill in the blanks. The gene has many versions, or alleles. Males inherit a single copy of the gene; bees that inherit two copies, each a different version, become female. Bees that have the misfortune of inheriting two identical copies of csd develop into sterile males but are quickly eaten at the larval stage by female worker bees.

The system works fine in nature, where it prevents the colony from wasting precious energy and resources on abnormal males incapable of carrying out the all-important role of mating. But in bees raised for honey or for pollinating crops, the sex-determination system can cause problems. Beekeepers inbreed bees to select desirable traits, but inbreeding raises the odds of producing fertilized eggs with two copies of the same csd allele. If too many sterile males result, the colony may die out.

"If we know more details about how many alleles there are and what their frequencies are, bee breeders can design better strategies to avoid producing sterile males," Zhang said. "Our work aids in this effort by providing a direct tool to examine alleles from different populations."

In the research, Zhang and coworkers from U-M, Michigan State University and the University of Kansas sequenced csd genes from individuals in three closely related species of honey bee: the familiar backyard denizen Apis mellifera and the Asian honey bees Apis dorsata and Apis cerana. The group also sequenced six so-called neutral regions of the genome which, unlike genes, do not carry codes telling cells how to make proteins. Then, the researchers constructed gene genealogies—family trees for both the csd gene and the neutral regions.

Their results showed that csd is about seven times more variable than neutral regions of the honey bee genome. In addition, many csd variants are shared among the three species, evidence that the many different alleles have been preserved in these lineages for a very long time.

Such a pattern supports the idea that an evolutionary mechanism known as balancing selection has been at work. Evolution works through the process of natural selection, in which genetic mutations that offer some advantage are favored, and those that have harmful effects are weeded out. Typically, this results in one version of a gene becoming very common and other versions becoming rare or disappearing altogether. When balancing selection operates, however, natural selection favors a diverse mix of alleles, as seen with csd in honey bees.

The research also showed just how long the csd alleles have been around.

"We estimated the age of the alleles at about 14 million years," said Zhang. "We don't know for sure when the species formed, but it's thought to be about six to eight million years ago, so the alleles are even older than the species."

Zhang collaborated on the research with postdoctoral fellow Soochin Cho and undergraduate student Daniel Green of the University of Michigan, Zachary Huang of Michigan State University and Deborah Smith of the Uni versity of Kansas. The researchers received financial support from the U-M Office of the Vice President for Research, the National Institutes of Health and the University of Kansas General Research Fund.


Related medicine news :

1. Breeding Mosquitoes Soon to be a Criminal Offence
2. AIIMS Campus - A Breeding Ground for Mosquitoes
3. Public Urged To Prevent Mosquito Breeding
4. Endangered species may be successfully cloned in another animals womb
5. Indian Prime Minister has successful Knee Replacement Surgery
6. Meningitis C vaccine a cost-effective success
7. Genetics linked to leukemia treatment success rate in children
8. Hope for Marburg treatment: vaccine successful in primates
9. Down syndrome simulated in animal model after successful chromosome transplantation
10. AIDS bias successfully overcome by Indian Muslims in South Africa
11. A success for the Indian pharmacy: gets licence to manufacture Tamiflu
Post Your Comments:

(Date:6/25/2016)... ... 2016 , ... As a lifelong Southern Californian, Dr. Omkar Marathe earned his ... David Geffen School of Medicine at UCLA. He trained in Internal Medicine at Scripps ... in hematology/oncology at the UCLA-Olive View-Cedars Sinai program where he had the opportunity to ...
(Date:6/25/2016)... ... ... Friday, June 10, Van Mitchell, Secretary of the Maryland Department of Health and Mental ... exemplary accomplishments in worksite health promotion. , The Wellness at Work Awards took place ... BWI Marriott in Linthicum Heights. iHire was one of 42 businesses to receive an ...
(Date:6/24/2016)... ... June 24, 2016 , ... A recent article ... are unfamiliar with. The article goes on to state that individuals are now more ... these less common operations such as calf and cheek reduction. The Los Angeles area ...
(Date:6/24/2016)... ... June 24, 2016 , ... June 19, 2016 is ... associated with chronic pain and the benefits of holistic treatments, Serenity Recovery Center ... suffering with Sickle Cell Disease. , Sickle Cell Disease (SCD) is a disorder of ...
(Date:6/24/2016)... ... 24, 2016 , ... The Pulmonary Hypertension Association (PHA) learned ... receive two significant new grants to support its work to advance research and ... by recognizing patients, medical professionals and scientists for their work in fighting pulmonary ...
Breaking Medicine News(10 mins):
(Date:6/24/2016)... HILL, N.C. , June 24, 2016 /PRNewswire/ ... healthcare decisions and regulators/payers have placed more emphasis ... new environment, patient support programs in the pharmaceutical ... for patients, medications. Consequently, pharmaceutical companies are focusing ... ensure they are providing products and services that ...
(Date:6/24/2016)... June 24, 2016 ... announced the addition of the " Global Markets ... This report focuses ... an updated review, including its applications in various applications. ... market, which includes three main industries: pharmaceutical and biotechnology, ...
(Date:6/24/2016)... and SAN CLEMENTE, Calif. , June ... -based mobile pulmonary function testing company, is now able to ... devices developed by ndd Medical Technologies , Inc. ... done in hospital-based labs.  Thanks to ndd,s EasyOne PRO ® , ... , can get any needed testing done in the comfort of ...
Breaking Medicine Technology: