Your brain may have forgotten, but what about your genes?

Among the seemingly unchangeable traits and predispositions people inherit from their families through their DNA, an expert said genes can also be altered by how people live, eat and relate to others.

Dr. Sharon Moalem explored the topic in his new book "Inheritance: How our genes change our lives and how our lives change our genes."

He gave the example of bullying, citing a recent study of identical twins where one of the siblings got bullied while the other did not.

"When you look at their DNA, you see these changes, off and on changes, these imprints on the DNA that happens with the bullying years later," Moalem said Thursday on "CBS This Morning." "You may have gotten over it psychologically, but your genes don't forget."

So if genes are prone to change, does that mean people with known mutations that predispose them to certain diseases - the BRCA gene, for example - can manipulate their genes to eliminate that risk? Moalem said there's no technology right now that allows people to rid themselves of the mutuation, but it's still important to trace back to relatives' medical histories.

"We often don't sit down with our families and say, 'What did Aunt May pass way from?' We don't draw out a family tree," Moalem said. "This is actually one of the most powerful things we can do is to figure out what our relatives actually had, what medical conditions they had because then we can reflect back and say are we at risk from the same conditions?"

He also said there are physical subtleties and clues, such as the distance between one's eyes or crooked pinkies, which could connect to genetic conditions. Watch his full interview above to find out more.