Navigation Links
History-hunting geneticists can still follow familiar trail

ntists believe was a common ancestral mother.

But over the eons, random mutations enter the genetic code of all species. By tracking similarities and differences of mtDNA, scientists gain insight about the size of groups and how they moved around the world.

"When you look at ancient migration, you're always asking the question, 'How big was the population, how many were there?'" said Michael Miyamoto, a professor and associate chairman of zoology in UF's College of Liberal Arts and Sciences. "The field has worked from the premise that the more mtDNA variation you saw, the larger the population was that carried that variation, just like there would be a greater diversity of T-shirts or shoes within a larger population than a smaller population."

However, the connection between mtDNA and population size was questioned this year when French scientists analyzed vast groups of gene sequences from more than 3,000 animal species. They speculated that an evolutionary tendency for species to keep helpful genes and sift out detrimental ones, called "natural selection," preferentially affects mitochondrial diversity, making mtDNA less useful for population size estimates.

"From a conservation perspective, when scientists look at census counts of animals and how the population size may be increasing or decreasing, the study of mtDNA tells us about the level of genetic diversity in a population, which is important in making conservation decisions on endangered species," Mulligan said. "If this approach were not credible, it could potentially have a bearing on future policy decisions, as well as affect literally hundreds of previous studies on humans and other mammals."

UF Genetics Institute scientists analyzed publicly available mtDNA datasets of 47 species of mammals -- a subset of the animals that were in the French study -- as well as associated data on protein diversity in the same species. A greater variety of proteins indic
'"/>

Source:University of Florida


Page: 1 2 3

Related biology news :

1. South Africa still debating how to tackle HIV/AIDS when 5 million are infected
2. Human brain is still evolving
3. Genetic testing still smart choice, despite uncertainties
4. Tuberculosis still a risk for patients receiving HIV drugs
5. DNA conclusive yet still controversial, Carnegie Mellon professor says
6. One-third of adults with diabetes still dont know they have it
7. Mice lacking key immune component still control chronic viral infections
8. Despite acidity, orange juice could still be a source of foodborne disease
9. Ten years later, Dolly is still making headlines
10. Experimental vaccine given during pregnancy reduces stillbirths from common virus
11. Amur leopard still on the brink of extinction, scientists say
Post Your Comments: