Yuseob Kim
Theoretical Population Genetics
Population genetics is concerned with the source and consequence of genetic variation among individuals. It attempts to explain the genetic basis of evolution. Much of this field is mathematical or computational because many questions of evolution are quantitative in nature.
My major subject of research has been the rate and strength of beneficial mutations in nature. Beneficial mutations are defined to increase the reproductive success. Unlike neutral and deleterious mutations, beneficial mutations occur too infrequently to be directly observed in a population sample. Therefore, it is necessary to infer their presence by finding the signature or footprint of beneficial mutations that arose in the past. When a beneficial allele increases rapidly in a population, it disturbs the dynamics of neutral and slightly deleterious alleles. We can thus find the signature of past beneficial mutations by examining the pattern of genetic variation among species in present-day samples. In my work, I develop mathematical models that aid in the process of detecting this signature. Although mainly theoretical, this work remains closely tied to observations of actual DNA sequence variation. In practical application, this study is used to infer locations of genes that are responsible for agronomic traits of domesticated plants.
I also study various models of evolution to find which genetic system (e.g. sexual vs. asexual, additive vs. epistatic, robust vs. non-robust) is important for biological adaptation in nature. Computer simulation is the major tool in this investigation.
Selected Publications
Kim, Y. (2006): Allele frequency distribution under recurrent selective sweeps, Genetics, in press.
Kim, Y. & Orr, H. A. (2005): Adaptation in sexuals vs. asexuals: clonal interference and the Fisher-Muller model, Genetics, 171:1377-1386.
Innan, H. & Kim, Y. (2004): Pattern of polymorphism after strong artificial selection in a domestication event, PNAS, 101:10667-10672.
Kim, Y. & Nielsen, R. (2004): Linkage disequilibrium as a signature of selective sweeps, Genetics, 167:1513-1524.
Kim, Y. (2004): Effect of strong directional selection on weakly selected mutations at linked sites: implication for synonymous codon usage, Molecular Biology and Evolution, 21:286-294.