Navigation Links
Geneticists discover genes that make fruit fly hybrids sterile

While hybrids -- the result of the mating of two different species -- may offer interesting and beneficial traits, they are usually sterile or unable to survive. For example, a mule, the result of the mating of a horse and a donkey, is sterile.

Now, Cornell researchers have made the first identification of a pair of genes in any species that are responsible for problems unique to hybrids. Specifically, the researchers have found two genes from two fruit fly species (Drosophila melanogaster and D. simulans) that interfere with each other, thereby preventing the production of male offspring.

The finding may eventually shed light on what causes lethality or sterility in hybrids in general and, in a larger sense, offers clues to how species evolve from common ancestors.

The research, published in the Nov. 24 issue of Science, focuses on a rarely occurring mutation in a D. melanogaster gene called "Hmr" (Hybrid male rescue) and a similar mutation in a D. simulans gene called "Lhr" (Lethal hybrid rescue) that make these genes nonfunctional. When either of these genes is "turned off" and then crossed with the other fruit fly species, the males survive.

"We have found the first example of two genes that interact to cause lethality in a species hybrid," said the paper's senior author, Daniel Barbash, assistant professor in Cornell's Department of Molecular Biology and Genetics.

The finding supports the Dobzhansky-Muller model, a theory from the 1930s that suggests hybrid incompatibilities (such as death or sterility) are caused by genes that have evolved from a common ancestor but diverged in each of the species. More specifically, in the common ancestor, these genes may have worked perfectly well together. But, as each gene evolved in its own species, it began to code for proteins that no longer work in the other species.

In this case, when genes from each species were compared with each other, the Hmr gene in D. melanogaster and the Lhr gene in D. simulans each evolved much faster than most other genes and diverged due to natural selection, a genetic change due to a pressure that benefits the survival of a species. The researchers would like to learn what these genes normally do within their species in order to understand why they are evolving so fast.

The Dobzhansky-Muller model also proposes that these evolved genes depend on each other to cause hybrid incompatibilities.

However, when Barbash and his colleagues cloned each gene and inserted an Lhr gene from D. simulans into D. melanogaster, the two genes did not interfere with each other in the engineered D. melanogaster strain even though the Lhr and Hmr genes interfere with each other in hybrids.

"This tells us there must be other things involved in the hybrid" that impacts the incompatible pairing of these genes, said Barbash. In future work the researchers hope to determine whether the hybrids die because of additional genes like Hmr and Lhr, or because of more subtle differences between the chromosomes of these two species.


'"/>

Source:Cornell University News Service


Related biology news :

1. UAB scientists discover the origin of a mysterious physical force
2. Researchers discover way to make cells in the eye sensitive to light
3. Protein discovery could unlock the secret to better TB treatment
4. Newly-discovered class of genes determines ?and restricts ?stem cell fate
5. Newly discovered virus linked to childhood lung disorders and Kawasaki disease
6. Purdue proves concept of using nano-materials for drug discovery
7. Scientists discover the cellular roots of graying hair
8. Researchers discover molecule that causes secondary stroke
9. Scientists discover unique microbe in Californias largest lake
10. New protein discovered by Hebrew University researchers
11. UCSD discovery may help extend life of natural pesticide
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:11/29/2016)... 29, 2016   Neurotechnology , a ... recognition technologies, today released FingerCell 3.0, a ... solutions that run on low-power, low-memory microcontrollers. ... less than 128KB of memory, enabling it ... have limited on-board resources, such as: mobile ...
(Date:11/22/2016)... , November 22, 2016 According to the new ... Palm Print, Face, Vein, Signature, Voice), Multi-Factor), Component (Hardware and Software), Function ... by MarketsandMarkets, the market is expected to grow from USD 10.74 Billion ... of 16.79% between 2016 and 2022. Continue ... ...
(Date:11/17/2016)... LONDON , Nov. 17, 2016 Global Market ... and Public Biobanks (Disease-Based Banks, Population-Based Banks and Academics) market ... Geographical analysis for Private Biobanks shows the highest Compounded Annual ... Asia-Pacific region during the analysis period 2014-2020. ... a CAGR of 9.95% followed by Europe ...
Breaking Biology News(10 mins):
(Date:12/8/2016)... 8, 2016  The Board of Directors of the ... Western Pennsylvania,s only pure life sciences investment ... with the succession plan developed by the Nominating and ... James (Jim) F. Jordan is selected to ... John W. Manzetti , who is elected to the ...
(Date:12/8/2016)... ... December 08, 2016 , ... From wearable devices that can ... sports. On Thursday, December 15th a panel of entrepreneurs, innovators and a Philadelphia ... at a Smart Talk session. Smart Talk will run from 8:30 – 10:30 ...
(Date:12/8/2016)... DES MOINES, Iowa , Dec. 8, 2016 Eurofins ... for US Food and President of Eurofins Scientific Inc. (ESI). ... Food Division with his proven professional and entrepreneurial experience in leading ... growth in the US food testing market to uphold Eurofins, status ... ...
(Date:12/8/2016)... , December 8, 2016 ... expanded its customisable SureSeq™ NGS panel range with the launch ... fast and cost-effective study of variants in familial hypercholesterolemia (FH). ... variation (CNV) detection on a single small panel and allows ... content. This includes all exons for LDLR , ...
Breaking Biology Technology: