%0 Journal Article
%T Characterization and potential functional significance of human-chimpanzee large INDEL variation
%A Nalini Polavarapu
%A Gaurav Arora
%A Vinay K Mittal
%A John F McDonald
%J Mobile DNA
%D 2011
%I BioMed Central
%R 10.1186/1759-8753-2-13
%X Extensive, large INDEL variation exists between the human and chimpanzee genomes. This variation is primarily attributable to retrotransposon insertions within the human lineage. There is a significant correlation between differences in gene expression and large human-chimpanzee INDEL variation mapping in genes or in proximity to them.The results presented herein are consistent with the hypothesis that large INDELs, particularly those associated with retrotransposons, have played a significant role in human-chimpanzee regulatory evolution.Although humans and chimpanzees have accumulated significant differences in a number of phenotypic traits since diverging from a common ancestor about six to eight million years ago, their genomes are more than 98.5% identical at protein-coding loci [1]. Since this modest degree of nucleotide divergence does not seem sufficient to explain the extensive phenotypic differences that exist between the two species, it has been hypothesized that the genetic basis of the differences lies at the level of gene regulation [2] and is associated with the extensive insertion and deletion (INDEL) variation between the two species [3].A number of comparative genomic studies focused on specific chromosomal regions of humans and nonhuman primates that have been carried out have revealed that significant INDEL variation exists between these species [4,5]. For example, in a comparison of human chromosome 21 and the syntenic chimpanzee chromosome 22, as many as 68,000 INDELs were identified [6]. We have shown previously that interspersed repeats, particularly retrotransposons (RTs), have contributed significantly to the INDEL variation between humans and chimpanzees [7]. Because RT sequences located in or near genes have the capacity to significantly alter patterns of gene expression, it has long been recognized that these elements may be important factors in regulatory evolution [8-16]. Other sources of INDEL variation between chimpanzees and humans
%K insertion and deletion
%K differential gene expression
%K retrotransposon
%K noninterspersed sequence
%K human insertion
%K short interspersed nuclear element
%U http://www.mobilednajournal.com/content/2/1/13