Subfunctionalisation may occur when a gene is duplicated, then both genes diverge and perform more specialised tasks, splitting up the task which the original gene performed. Neofunctionalisation is where a gene becomes duplicated, then the duplicate becomes co-opted for an entirely different purpose. However, evolution seems to have other uses for duplicate genes...
GENE CLASSES FOLLOW DIFFERENT FATES AFTER PLANT GENOME DUPLICATION
By Heather Ramsey
The Science Creative Quarterly
Issue 2, Sep - Nov 2006
http://www.scq.ubc.ca/?p=596
Multiple copies of a mystery gene may make us human
From mice to monkeys to chimps to people, a brain-protein gene pumps up.
Bio Ed Online, August 31, 2006
http://www.bioedonline.org/news/news.cfm?art=2760
A gene that makes us human?
Saturday, September 02, 2006
http://pharyngula.org/index/weblog/comm ... _us_human/
Identification by full-coverage array CGH of human DNA copy number increases relative to chimpanzee and gorilla
Gary M. Wilson, Stephane Flibotte, Perseus I. Missirlis, Marco A. Marra, Steven Jones1, Kevin Thornton, Andrew G. Clark and Robert A. Holt
Genome Research 16:173-181, 2006
http://www.genome.org/cgi/content/full/16/2/173
Punctuated duplication seeding events during the evolution of human chromosome 2p11
Julie E. Horvath, Cassandra L. Gulden, Rhea U. Vallente, Marla Y. Eichler, Mario Ventura, John D. McPherson, Tina A. Graves, Richard K. Wilson, Stuart Schwartz, Mariano Rocchi and Evan E. Eichler
Genome Research 15:914-927, 2005
http://www.genome.org/cgi/content/full/15/7/914