Navigation Links
East African cichlid fish offer new understanding of genetic basis of sex determination
Date:10/1/2009

Biologists have genetically mapped the sex chromosomes of several species of cichlid fish from Lake Malawi, East Africa, and identified a mechanism by which new sex chromosomes may evolve.

In research published in this week's issue of the journal Science, biologists Thomas Kocher, Reade Roberts and Jennifer Ser of the University of Maryland describe the genetic basis for two co-existing systems of sexual determination in cichlid fish from Lake Malawi.

"This study marries two evolutionary mysteries: the incredible diversity of fish in the lakes of East Africa and the genetic basis of sex determination," says Sam Scheiner, program director in the National Science Foundation (NSF)'s Division of Environmental Biology, which funded the research. "Simple genetic changes can lead to enormous biological diversity."

In nearly all mammals, the SRY gene determines the sex of offspring and is located on the Y chromosome, which is much smaller than the X chromosome.

But in many other animal groups, the genetic mechanism of sex determination evolves quite rapidly, and the differences between sex chromosomes are harder to observe.

Even sister species of fish may have entirely different sex determination systems. How and why the genetic mechanisms for such an ancient developmental distinction continue to evolve has remained a mystery.

The thousands of closely related cichlid fishes in the lakes of East Africa turn out to be an excellent model system for understanding how the mechanisms of sex determination evolve.

The East African cichlid fishes that inhabit Lakes Malawi, Tanganyika, and Victoria are known for their sexually distinct appearance--the males are generally conspicuous and brightly colored, making them more attractive to females, while the females are drab and brown, making them inconspicuous to predators.

One exception to the uniformly brown pigmentation among female cichlids is the "or
'/>"/>

Contact: Cheryl Dybas
cdybas@nsf.gov
703-292-7734
National Science Foundation
Source:Eurekalert

Page: 1 2

Related biology news :

1. Google Earth aids discovery of early African mammal fossils
2. Going bananas for sustainable research -- scientists create fuel from African crop waste
3. Difference in fat storage may explain lower rate of liver disease in African-Americans
4. Cleaning the atmosphere of carbon: African forests out of balance
5. Ancestral genome of present-day African great apes & humans had burst of DNA sequence duplication
6. African-Americans aware and accepting, but often do not receive, the HPV vaccine
7. Nutritional supplementation program helps prevent weight loss among children in African country
8. African thicket rat malaria linked to virulent human form
9. Ancient African exodus mostly involved men, geneticists find
10. Ecological impact of African cities
11. Hypertension develops early, silently, in African-American men
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:7/11/2014)... University, Sweden, have explored two different ways that ... leading to the formation of oxygen molecules in ... the scientific journal Nature Communications . , ... synthetic catalysts for water oxidation, which are key ... direct storage of solar energy in fuels like ...
(Date:7/11/2014)... 11, 2014 The increased risk of kidney injury ... resuscitation fluids reflects the mass of HES molecules, according ... official journal of the International Anesthesia Research Society (IARS). ... harmful effect of HES on cultured human renal proximal ... Christian Wunder and colleagues of University Hospital Wrzburg, Austria. ...
(Date:7/11/2014)... the hippocampus, the marginal division of the striatum ... is the impact degree of substance P in ... function? Yan Yu and his team, College of ... immunofluorescence staining, that substance P receptor, neurokinin 1 ... marginal division of normal rats. Unilateral or bilateral ...
Breaking Biology News(10 mins):Molecular snapshots of oxygen formation in photosynthesis 2In lab studies, hydroxyethyl starch has direct harmful effects on kidney cells 2
... (VICC) has launched the nation,s first personalized cancer ... physicians and researchers track the latest developments in ... trials for their patients. This web-based ... quickly educate clinicians on the rapidly expanding list ...
... engineering, microcompartments molecular shells made of proteins ... tiny home for important reactions. In bacterial organelles, ... dioxide and convert it into sugar as an ... a specialized 20-sided shape called an icosahedron. But ...
... Cancer patients are willing to undergo many tests ... to a new study by Mayo Clinic, Scottsdale Healthcare ... said patients, willingness to undergo tests bodes well for ... are prescribed depending on the DNA genetic makeup of ...
Cached Biology News:Vanderbilt-Ingram Cancer Center launches online genetic research tool 2Researchers discover new shapes of microcompartments 2Patients are willing to undergo multiple tests for new cancer treatments 2Patients are willing to undergo multiple tests for new cancer treatments 3
(Date:7/10/2014)... 10, 2014  Franciscan St. Anthony Health-Crown ... for respiratory monitoring outside the operating room, ... in embracing state-of-the-art patient safety technology. ... breathing and can alert medical caregivers when ... amount of carbon dioxide the patient is ...
(Date:7/10/2014)... OAKS, Calif., July 10, 2014   Ceres, Inc ... and seed company, announced today financial results for the ... update on its business. Ceres reported that ... in product performance this growing season in Brazil, which ... affected the company,s sorghum evaluation areas for part of ...
(Date:7/10/2014)... extremely challenging because there are many genetic variants that ... Now investigators reporting in the July 3rd issue of ... describe a strategy that may help reveal how such ... environmental exposures to affect the development of the nervous ... predispose individuals to schizophrenia. , The work takes ...
(Date:7/10/2014)... the University of Illinois at Urbana-Champaign provides new ... of spin and heat at the nanoscale, and ... for data storage and information processing. , ... momentum. In a typical charge current, electrons, spin-angular-momentum ... explained David Cahill, a professor of materials science ...
Breaking Biology Technology:Franciscan St. Anthony Health-Crown Point Underscores Patient Safety Commitment Through Expanded Use of Capnography 2Ceres Announces Fiscal Third Quarter 2014 Financial Results 2Ceres Announces Fiscal Third Quarter 2014 Financial Results 3Ceres Announces Fiscal Third Quarter 2014 Financial Results 4Ceres Announces Fiscal Third Quarter 2014 Financial Results 5Ceres Announces Fiscal Third Quarter 2014 Financial Results 6Ceres Announces Fiscal Third Quarter 2014 Financial Results 7Ceres Announces Fiscal Third Quarter 2014 Financial Results 8Ceres Announces Fiscal Third Quarter 2014 Financial Results 9New strategy could uncover genes at the root of psychiatric illnesses 2University of Illinois study advances limits for ultrafast nano-devices 2
... the IT industry is gripped in a mania for centralization right ... black, but since it's technology, I'll have to settle for saying ... some serious competition as the option of first resort when it ... might not fly in the states of Kansas or Ohio, this ...
... significance of this past Sunday? , ,Yes, it was Mother's ... Day ("Victory in Europe"), but it was also the 106th ... of the world's greatest economists. These days, while Hayek is ... seminal work "The Road to Serfdom," he was also a ...
... situation is exciting at the beginning. , ,Two companies ... a new Web site, or have a service provider deliver ... these contracts work out perfectly well and the parties come ... work that has been performed or received. , ,However, ...
Cached Biology Technology:Centralization mania takes over 2Centralization mania takes over 3Centralization mania takes over 4Midwest cities in fight over municipal broadband access 2Midwest cities in fight over municipal broadband access 3Midwest cities in fight over municipal broadband access 4Arbitration can help when IT deals go sour 2Arbitration can help when IT deals go sour 3
... using advanced automated high throughput microplate processing equipment that dispenses ... accommodate virtually any lot size of the following formats (with ... 8 and 12 well strips, ... 384 well microplate, 1536 ...
... are based on well-established periodate chemistry, ... and reproducible. This kit contains all ... or antibody, including ready-to-use buffers and ... HRP is supplied ready-to-use and requires ...
... Acridinium NHS ester can be ... nucleic acids. The covalently bound ... chemiluminescence in the presence of ... proteins can be used as ...
... hold up to 6 strain chambers with precise ... use design ensures that cells grow over long ... compression. This unit allows you to control the ... 64 unique strain settings. The instrument fits in ...
Biology Products: