Adult genetic engineering would not be inheritable. Your gonads produce variations of genetic material based on their own blueprints (which come from you parents, not your genes).

See: http://en.wikipedia.org/wiki/Germline

http://www.nature.com/news/a-slippery-slope-to-human-germlin...

http://www.dnapolicy.org/pub.reports.php?action=detail&repor...