TY - JOUR
T1 - Correlation analyses reveal a substantial influence of allelic gaps on the investigation of genetic diversity of modern human populations with microsatellites
AU - Guha, Saurav
AU - Chakraborty, R.
PY - 2008
Y1 - 2008
N2 - High intra-population genetic diversity and multiple measures of genetic variability at STR loci are useful in inferring past evolutionary history. However, STRs, categorized by their repeat motif size, differ in a number of aspects, requiring separate analyses. We analyzed 783 STRs in 36 worldwide populations to examine marker suitability as well as correlations between various measurements, to evaluate the extent of genomic diversity present in modern human populations. The loci were grouped by type and analyzed separately for each population group. Genetic variation defined by gene diversity and allele size variance, shows different trends of variation across four types of STRs. Additionally, there is little variation of genetic diversity, but there is decreased allelic size variance with increasing repeat motifs. A poor correlation between genetic diversity and allelic size variance across loci in all groups for Di-STRs is probably caused by the presence of allelic size gaps. In contrast, allelic size variance, genetic diversity, and number of alleles are strongly correlated with both tri- and tetra-STRs. The positive correlation of allelic size variance and presence of gaps within the range of allelic sizes in Di-STRs alone explains these observations. An unexpected high imbalance index (β) at Di-STRs due to high allelic size variance also supports this assertion.
AB - High intra-population genetic diversity and multiple measures of genetic variability at STR loci are useful in inferring past evolutionary history. However, STRs, categorized by their repeat motif size, differ in a number of aspects, requiring separate analyses. We analyzed 783 STRs in 36 worldwide populations to examine marker suitability as well as correlations between various measurements, to evaluate the extent of genomic diversity present in modern human populations. The loci were grouped by type and analyzed separately for each population group. Genetic variation defined by gene diversity and allele size variance, shows different trends of variation across four types of STRs. Additionally, there is little variation of genetic diversity, but there is decreased allelic size variance with increasing repeat motifs. A poor correlation between genetic diversity and allelic size variance across loci in all groups for Di-STRs is probably caused by the presence of allelic size gaps. In contrast, allelic size variance, genetic diversity, and number of alleles are strongly correlated with both tri- and tetra-STRs. The positive correlation of allelic size variance and presence of gaps within the range of allelic sizes in Di-STRs alone explains these observations. An unexpected high imbalance index (β) at Di-STRs due to high allelic size variance also supports this assertion.
KW - Allele size variance
KW - Allelic gap
KW - Genetic diversity
KW - Heterozygosity
KW - Imbalance index
KW - STR
UR - http://www.scopus.com/inward/record.url?scp=49449097986&partnerID=8YFLogxK
U2 - 10.1111/j.1469-1809.2008.00445.x
DO - 10.1111/j.1469-1809.2008.00445.x
M3 - Article
C2 - 18460049
AN - SCOPUS:49449097986
SN - 0003-4800
VL - 72
SP - 644
EP - 653
JO - Annals of Human Genetics
JF - Annals of Human Genetics
IS - 5
ER -