By Kevin Davies
March 8, 2005 | In another example of the power of comparative genomics, scientists at the European Molecular Biology Laboratory (EMBL) in Heidelberg, Germany, have identified a new primate-specific gene family that spans about 10 percent of human chromosome 2 and illustrates how genes have evolved and acquired new functions during evolution.
Gene duplication is known to be a strong driver of evolution. Acquiring extra copies of genes can be detrimental to an organism's health, and evolution frequently counters the dosage problem by converting the extra copies into nonfunctional "pseudogenes." However, in some cases, this gene redundancy also provides the opportunity for extra copies to potentially acquire new functions, and hence confer a selective advantage to an organism.
|Featured Report: Ciccarelli, F.D.; von Mering, C.; Suyama, M.; Harrington, E.; Izaurralde, E.; and Bork, P. "Complex genomic rearrangements lead to novel primate gene function." Genome Research 15, 343-51; 2005.
Reporting in the online edition of Genome Research, Peer Bork and colleagues set out to find examples of this phenomenon by systematically comparing the genomes of several species for examples of single genes that are present in multiple copies in primates.
The EMBL bioinformaticians found 22 genes that fit those criteria, including a gene called RanBP2. This gene codes for a large protein that regulates traffic of nucleic acids and proteins in and out of the nucleus.
In humans, the new gene family spans a striking 10 percent of human chromosome 2, which was formed millions of years ago by the fusion of two ape chromosomes. The gene family acquired a domain from the neighboring GCC2 gene, which has a function in the cytoplasm. The new gene family has eight members, and is named RGP (for RanBP2-like, GRIP domain-containing proteins).