Q. I’m fascinated by what I’m learning about cellular memory. Couldn’t epigenetics explain being gay?

A. Epigenetics or cellular memory is a fascinating topic. Scientists have become convinced that there is a form of inheritance in which the behavior of genes in offspring is affected by the life experience of parents. Or to put it another way, epigenetic factors may influence whether specific genes are turned on or turned off. According to some, epigenetics is one of the most scientifically important, and legally and ethically significant, cutting-edge subjects of scientific discovery.

Epigenetics link environmental and genetic influences with traits and characteristics of an individual, and new discoveries reveal that a potentially large range of environmental, dietary, behavioral, cultural, personality, psychiatric traits, and medical experiences can significantly affect the future development and health of an individual and their offspring. This means that in practice parents can pass along attributes they have acquired through experience to their biological children and grandchildren (although at this point the effects do not appear to last indefinitely).

In an article published in the UK entitled “What Genes Remember,” author Phillip Hunter writes: “Historical insults, such as Oliver Cromwell's brutal reconquest of Ireland in 1649, have led to an embedding of attitudes within the affected communities that persist for generations.” This is now being linked with cellular memory. In a similar way, historical traumas such as transatlantic slavery and the holocaust likely leave some type of cellular memory mark on descendants.

Epigenetic inheritance does not involve rewriting genes, however. Neither does it remove personal choice. Yes, a person may experience something or change a preference based on cellular memory (e.g., A child has nightmares about being killed after receiving the heart of a child who was murdered. A girl becomes pregnant at the age of 15, the age her mother became pregnant with her, even though the girl didn’t conscious know that fact. A boy tries to hang himself repeatedly without ever being told that his grandfather suicided by hanging when the boy’s mother was 5 months pregnant with him—and when given that information made no further attempts to hang himself. An adult male craves Snickers after receiving the heart of a 14-year-old boy who loved Snickers. Infants tend to prefer foods that their mothers ate during pregnancy). In adulthood, whether or not the person decides to eat Snickers or the foods their mother loved, boils down to personal choice.

While there may be potential effects related to epigenetic factors impacting gene expression in relation to homosexuality, I’ve not seen definitive research to date.