On the move | Eureka! Science News: "Rather than sticking to a single DNA script, human brain cells harbor astonishing genomic variability, according to scientists at the Salk Institute for Biological Studies. The findings, to be published in the Aug. 5, 2009, advance online edition of Nature, could help explain brain development and individuality, as well as lead to a better understanding of neurological disease. The team, led by Fred Gage, Ph.D., a professor in the Salk's Laboratory of Genetics and holder of the Vi and John Adler Chair for Research on Age-Related Neurodegenerative Diseases, found that human brain cells contain an unexpected number of so-called mobile elements—extraordinary pieces of DNA that insert extra copies of themselves throughout the genome using a 'copy and paste' mechanism."
Add this to the AAA story, how does this affect stem cells?