Genetics, Vol. 168, 383-395, September 2004, Copyright © 2004
doi:10.1534/genetics.103.022665

Microsatellite Mutation Models

Insights From a Comparison of Humans and Chimpanzees

* Department of Statistical Science, Cornell University, Ithaca, New York 14853
{dagger} Department of Mathematics, Cornell University, Ithaca, New York 14853
{ddagger} Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853
§ Department of Biological Statistics and Computational Biology, Cornell University, Ithaca, New York 14853

1 Corresponding author: Department of Statistical Science, 301 Malott Hall, Cornell University, Ithaca, NY 14853.
E-mail: rs228{at}cornell.edu

Using genomic data from homologous microsatellite loci of pure AC repeats in humans and chimpanzees, several models of microsatellite evolution are tested and compared using likelihood-ratio tests and the Akaike information criterion. A proportional-rate, linear-biased, one-phase model emerges as the best model. A focal length toward which the mutational and/or substitutional process is linearly biased is a crucial feature of microsatellite evolution. We find that two-phase models do not lead to a significantly better fit than their one-phase counterparts. The performance of models based on the fit of their stationary distributions to the empirical distribution of microsatellite lengths in the human genome is consistent with that based on the human-chimp comparison. Microsatellites interrupted by even a single point mutation exhibit a twofold decrease in their mutation rate when compared to pure AC repeats. In general, models that allow chimps to have a larger per-repeat unit slippage rate and/or a shorter focal length compared to humans give a better fit to the human-chimp data as well as the human genomic data.




This article has been cited by other articles:


Home page
GeneticsHome page
A.-L. Raquin, F. Depaulis, A. Lambert, N. Galic, P. Brabant, and I. Goldringer
Experimental Estimation of Mutation Rates in a Wheat Population With a Gene Genealogy Approach
Genetics, August 1, 2008; 179(4): 2195 - 2211.
[Abstract] [Full Text] [PDF]


Home page
GeneticsHome page
K. Zhang and N. A. Rosenberg
On the Genealogy of a Duplicated Microsatellite
Genetics, December 1, 2007; 177(4): 2109 - 2122.
[Abstract] [Full Text] [PDF]


Home page
J HeredHome page
F. Lopez-Giraldez, J. Marmi, and X. Domingo-Roura
High Incidence of Nonslippage Mechanisms Generating Variability and Complexity in Eurasian Badger Microsatellites
J. Hered., September 1, 2007; 98(6): 620 - 628.
[Abstract] [Full Text] [PDF]


Home page
Mol Biol EvolHome page
A. R. Hoelzel, J. Hey, M. E. Dahlheim, C. Nicholson, V. Burkanov, and N. Black
Evolution of Population Structure in a Highly Social Top Predator, the Killer Whale
Mol. Biol. Evol., June 1, 2007; 24(6): 1407 - 1415.
[Abstract] [Full Text] [PDF]