title: Mutation patterns at dinucleotide microsatellite loci in humans.
abstract: Microsatellites are a major type of molecular markers in genetics studies. Their mutational dynamics are not clear. We investigated the patterns and characteristics of 97 mutation events unambiguously identified, from 53 multigenerational pedigrees with 630 subjects, at 362 autosomal dinucleotide microsatellite loci. A size-dependent mutation bias (in which long alleles are biased toward contraction, whereas short alleles are biased toward expansion) is observed. There is a statistically significant negative relationship between the magnitude (repeat numbers changed during mutation) and direction (contraction or expansion) of mutations and standardized allele size. Contrasting with earlier findings in humans, most mutation events (63%) in our study are multistep events that involve changes of more than one repeat unit. There was no correlation between mutation rate and recombination rate. Our data indicate that mutational dynamics at microsatellite loci are more complicated than the generalized stepwise mutation models.
authors.affiliation: Osteoporosis Research Center and Department of Biomedical Sciences, Creighton University, Omaha, NE 68131, USA.
authors.forename: Qing-Yang
authors.initials: QY
authors.lastname: Huang
authors.forename: Fu-Hua
authors.initials: FH
authors.lastname: Xu
authors.forename: Hui
authors.initials: H
authors.lastname: Shen
authors.forename: Hong-Yi
authors.initials: HY
authors.lastname: Deng
authors.forename: Yong-Jun
authors.initials: YJ
authors.lastname: Liu
authors.forename: Yao-Zhong
authors.initials: YZ
authors.lastname: Liu
authors.forename: Jin-Long
authors.initials: JL
authors.lastname: Li
authors.forename: Robert R
authors.initials: RR
authors.lastname: Recker
authors.forename: Hong-Wen
authors.initials: HW
authors.lastname: Deng
mesh_terms: D000483:Alleles; D015982:Bias; D002875:Chromosomes / Q000235:genetics; D004252:DNA Mutational Analysis; D018900:Dinucleotide Repeats / Q000235:genetics*; D005260:Female; D006801:Humans; D007700:Kinetics; D008297:Male; D008957:Models, Genetic; D016296:Mutagenesis / Q000235:genetics*; D010375:Pedigree; D011995:Recombination, Genetic / Q000235:genetics