Fascination with physical traits that are recognizable from one generation to another is nothing new. But the desire to go beyond subjective comparisons is at an all-time high. Advances in next-gen sequencing have spawned companies promising to suss out our Neanderthal percentage and/or our risk of acquiring any number of diseases. In this issue Oliver Rando (“Ghosts in the Genome”) outlines an entirely different method of trait transmission, called transgenerational epigenetic inheritance, that depends on alterations that do not affect the DNA sequence itself. The idea has long been controversial, but evidence is accumulating that a male’s or a female’s experience—be it stress, diet, or exposure to toxic substances—can affect future generations. Focusing on the paternal side of the equation, Rando discusses evidence from mouse studies that fathers can pass on more than just a haploid genome, including epigenetic marks on DNA that do not get completely erased after fertilization; small, noncoding RNAs; and even active seminal fluid factors.
“Cellular Rehab” concerns the generational process, but in a completely different way. While the prime example of epigenetic inheritance is the production of committed cell types, such as liver or skin, the underlying premise of stem cell therapies is to encourage a less-committed cell type to regenerate damaged tissues or organs. Elie Dolgin, a news editor at the newly launched STAT, describes the new field of regenerative rehabilitation, which combines the benefits of cell and physical therapies. Transplanting muscle stem cells into mice that are then made to exercise, or mechanically stretching the cells before transplantation, can enhance muscle growth and strength.
Citation of scientific journal articles is also a form of inheritance, and errors or deliberate misrepresentations that aren’t corrected are like deleterious mutations that distort the transmission of knowledge. A trio of articles looks at the problem of retraction from several different angles. In “Scientific Misconduct: Red Flags,” attorney John R. Thomas Jr. outlines telltale signs that could ultimately result in flawed publications, and offers some guidance about what to do if you suspect a colleague of devious behavior. Retractions can result from a number of different problems, not all of them related to author misconduct. Once the need for retraction arises, however, there exists no accepted standard for how to handle the process, write Hervé Maisonneuve and Evelyne Decullier, who argue for the adoption of a simple form that would allow the writing of clearer, more informative retraction notices. And in a Careers article, “Self Correction,” Associate Editor Kerry Grens takes a look at how to go about retracting one’s own article(s) after realizing that errors necessitate such a step.
Finally, 2015 wouldn’t be complete without listing the winners of our eighth annual Top Ten Innovations competition. The exciting new products that earned top spots in the minds of our independent judges include reagent kits that characterize energy profiles and immune states, a light microscope that can peer deep into living cells with 3-D detail, and even a next-gen sequencer for the forensic laboratory fully capable of proving the relationship between me and my children.
Catch you next year.
Mary Beth Aberlin Editor-in-Chief