Reversals of fetal expression changes are also seen again much later in life during normal aging of the brain. Additionally, the team observed the reversal of fetal expression changes in Alzheimer's disease findings reported in other studies. The research team also found that gene expression change is fastest in human brain tissue during fetal development, slows down through childhood and adolescence, stabilizes in adulthood, and then speeds up again after age 50, with distinct redirection of expression changes prior to birth and in early adulthood.
Using a number of genomic analysis technologies, the research team conducted genome-wide genetic (DNA) and gene expression (RNA) analyses of brain tissue samples from the prefrontal cortex. Tissue represented the various stages of the human lifespan.
The research also showed that brain gene expression differences between genetically diverse individuals (of different races, for example) are no greater than the differences between individuals sharing many more genetic traits.
