We already know that the genetic code is amazingly dense but most of it consists of "non coding regions", now the story is coming clear....it is a hierarchical code. Most of it is devoted to developmental pathway ('how long to grow or release it') as opposed to description pathways ('what to grow or release') it turns out that these rules are packaged (encapsulated is the word we use in OO programming which is amazingly analogous to the biological process) very nicely in the form of stem cells which are essentially factories for producing the somatic cells that form the normal population of most tissues, but another paper from last year showed that stem cells have only a few switches that allow them to produce differentiated cells of specific tissue types and even more awesome, is that those switches can be compared between stem cells to determine the key factors that make a heart stem cell different from a glioma or a lung tissue cell across the much smaller (thankfully) set of stem cells (a couple hundred!) that end up producing all the differentiated cells that make us up. Much like in the old analog tv sets where a tuner was used to select frequency in a given channel range and thus change the station, stem cells seem to do something similar modulating specific genes and thus modifying the downlevel genes that are expressed in a cascade to realize a given differentiated tissue, apparently some stem cells are root stem cells and others are downlevel (producing differentiated cells in given tissues)...it may sound complex but the hierarchical nature (similar systems ensure the internet is able to efficiently route data between billions of connected nodes at different levels of the OSI stack!) will effect a very rapid determination of the relationships and illumination of the expression pathways (and will help fully explain the seemingly impossible process of in vivo gene modulations that occur like transposon and retrotransposon actions, rna transcription..all while the cell is running!)
I predict a very rapid acceleration of findings regarding the relationships between known and to be found stem cells and how the expression can be modulated by other low level controls. Deciphering all the facts on this front in skin because of its cosmetic potential are likely going to be the first (for example it's known that collagen break down leads to wrinkles...thus by figuring out how and then effecting a reversal treatment genetically..wrinkles can be cured as an age associated pathology) thus we won't achieve virtual immortality as some grand achievement it will be a slow process of incremental developments effecting tissues more and more critical to survival (heart, break, lung, liver...etc.) as those tissue types are fully explored and explained from the genetic (and not the even more complex physiological) perspective. I expect the majority of results to come over the next 20 years.
http://www.nature.com/nature/journal/v463/n7278/abs/nature08629.html (1 mutation per cigarette paper)
http://www.novell.com/info/primer/prim05.html (Novell primer on the OSI stack and it's efficient hierarchy of hierarchical protocols and methods for communication on the internet)