Spring 2002
Tuesdays 12:15 Goldwater 604
(Supported in part by the Systems Science and Engineering Research Center)
Seminar Schedule:<http://math.la.asu.edu/~tom/cognition/math+cogsched.html>
The Mathematics and Cognition Seminar, will
present our next lecture on Tuesday, April 2, at 12:15 PM in GWC 604.
Our speaker will be Dr. Root Gorelick of the Department of Biology,
who will speak on the topic:
"Mathematical modeling of the effects of DNA methylation over evolutionary time"
Abstract.
| Biologists invoke the Muller's ratchet model to estimate rates at which the minimum number
of mutations in a population grows over evolutionary time. Two exogenous variables that drive
Muller's ratchet are rates of point mutations and recombination. I am building an
extension of Muller's ratchet in which point mutation and recombination rates are both functions
of the amount of methylation in the genome. Increased methylation levels cause a geometric increase in the speed with which point mutations accumulate. After this, I want to build a model in which methylation levels and genome lengths are also determined endogenously. I have specifying generative rules for a formal language to generate all possible chromosomes that could evolve. I also want to formulate this as a Markov model in which expected methylation levels and genome lengths can be computed over evolutionary time and possibly integrated with Muller's ratchet. Together these models could allow prediction of expected numbers of accumulated mutations (important in predicting susceptibility to carcinogens), rates of molecular clocks, when lineages can no longer survive without sex, and other macroevolutionary epigenetic phenomena. |