ANDRZEJ KRAUZEHolidays are synonymous with family gatherings. Multiple generations eat themselves into a stupor, and sparks of family tension frequently fly, kindled by old sibling rivalries or the often-fraught in-law relationship. Speaking of in-laws, one of my most memorable holiday meals was the Christmas when my mother-in-law looked across the dining room table and asked me, “How does it feel to have three children who look nothing like you?” Many years later, if she hadn’t been 98 and somewhat addled, she surely would have said something of that ilk to our daughter when, holding her days-old great-granddaughter in her lap, my mother-in-law posed for a photo that captured four generations.
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 ...
