mtDNA

[EmptySky]

Hi,

I'm trying to understand mtDNA mutation rates and would be grateful of some guidance.

Is it correct that mtDNA mutations are regular and predictable - a bit like clockwork - so that if I had a strand of mtDNA from a currently alive human I could determine exactly what a direct ancestor's mtDNA of that strand would have looked like if that ancestor existed, say, ten thousand or one hundred thousand years ago?

Any help appreciated!

DZ

[magicsiew]

mtDNA is maternal inherited, means we get the mtDNA from our mother only (with few exception is paternal inherited only). But I dont think we can trace back to 10k years ago, this is because there are other factors that may cause mtDNA variation

http://www.ncbi.nlm.nih.gov/pmc/article ... =pmcentrez

[Darby]

The "regular" rate of mtDNA point mutations is a uniformitarian assumption - the best someone can do until more data comes in. There is already some indication that it varies among different organisms.

[DRT23]

Once, I came across the information that mtDNA has only one site that is changed by mutations over time. This is probably because other sequences are vital and any mutatiton on this sites can cause death of mithocondria. I am not sure of this information's accuracy, but if it's true, tracing mtDNA variations back to ancient people may be easier. But, I think it's not still possible to predict exact sequences of a man lived thousands years ago.

[angel92]

Susceptibility

mtDNA is particularly susceptible to reactive oxygen species generated by the respiratory chain due to its close proximity. Though mtDNA is packaged by proteins and harbors significant DNA repair capacity, these protective functions are less robust than those operating on nuclear DNA and therefore thought to contribute to enhanced susceptibility of mtDNA to oxidative damage.
Genetic illness
Mutations of mitochondrial DNA can lead to a number of illnesses including exercise intolerance and Kearns-Sayre syndrome (KSS), which causes a person to lose full function of heart, eye, and muscle movements. Some evidence suggests that they might be major contributors to the aging process and age-associated pathologies.