PMID- 12082133
OWN - NLM
STAT- MEDLINE
DCOM- 20021216
LR  - 20180109
IS  - 0737-4038 (Print)
IS  - 0737-4038 (Linking)
VI  - 19
IP  - 7
DP  - 2002 Jul
TI  - Searching for evidence of positive selection in the human genome using patterns 
      of microsatellite variability.
PG  - 1143-53
AB  - Both natural selection and nonequilibrium population-level processes can lead to 
      a skew in the frequency distribution of polymorphisms. Population-level processes 
      are expected to affect all loci in a roughly equal fashion, whereas selection 
      will affect only some regions of the genome. We conducted a sliding-window 
      analysis of the frequency distribution of microsatellite polymorphisms across the 
      human genome to identify regions that may be under positive selection. The 
      analysis was based on a published data set of 5,257 mapped microsatellites in 
      individuals of European ancestry. Observed and expected numbers of alleles were 
      compared under a stepwise mutation model (SMM) using analytical formulae. 
      Observed and expected heterozygosities were compared under a SMM using coalescent 
      simulations. The two sets of analyses gave similar results. Approximately 
      one-fourth of all loci showed a significant deficit of heterozygosity, consistent 
      with a recent population expansion. Forty-three windows were identified with 
      extreme skews in the frequency distribution of polymorphisms (in the direction of 
      a deficit of heterozygosity, given the number of alleles). If these extreme 
      windows are tracking selection at linked sites, theory predicts that they should 
      be more common in regions of the genome with less recombination. We tested this 
      prediction by comparing recombination rates in these extreme windows and in other 
      regions of the genome and found that extreme windows had a significantly lower 
      recombination rate than the genomic average. The proportion of extreme windows 
      was significantly higher on the X chromosome than on the autosomes. Moreover, all 
      the windows with extreme skews on the X chromosome were found in two clusters 
      near the centromere; both these clusters exhibit markedly reduced recombination 
      rates. These analyses point to regions of the genome that may recently have been 
      subject to positive selection. These results also suggest that the effects of 
      positive selection may be more pronounced on the X chromosome than on the 
      autosomes in humans.
FAU - Payseur, Bret A
AU  - Payseur BA
AD  - Department of Ecology and Evolutionary Biology, Biosciences West Building, 
      University of Arizona, Tucson, Arizona 85721, USA. payseur@email.arizona.edu
FAU - Cutter, Asher D
AU  - Cutter AD
FAU - Nachman, Michael W
AU  - Nachman MW
LA  - eng
PT  - Journal Article
PT  - Research Support, U.S. Gov't, Non-P.H.S.
PL  - United States
TA  - Mol Biol Evol
JT  - Molecular biology and evolution
JID - 8501455
RN  - 0 (Genetic Markers)
SB  - IM
MH  - Alleles
MH  - Animals
MH  - Chromosome Mapping
MH  - Chromosomes/*genetics
MH  - Genetic Markers
MH  - *Genetic Variation
MH  - Genetics, Population
MH  - *Genome, Human
MH  - Haplotypes
MH  - Humans
MH  - Linkage Disequilibrium
MH  - Microsatellite Repeats/*genetics
MH  - *Models, Genetic
MH  - Mutation
MH  - Polymorphism, Genetic
MH  - Recombination, Genetic
MH  - *Selection, Genetic
MH  - X Chromosome
EDAT- 2002/06/26 10:00
MHDA- 2002/12/18 04:00
CRDT- 2002/06/26 10:00
PHST- 2002/06/26 10:00 [pubmed]
PHST- 2002/12/18 04:00 [medline]
PHST- 2002/06/26 10:00 [entrez]
AID - 10.1093/oxfordjournals.molbev.a004172 [doi]
PST - ppublish
SO  - Mol Biol Evol. 2002 Jul;19(7):1143-53. doi: 
      10.1093/oxfordjournals.molbev.a004172.