"When someone in the family begins to use drugs, we see everyone else assume certain roles, and these roles only support the drug use," [Michael Wood] said.

"Research has led us now to a genetic predisposition, which so often leads to drug abuse," Wood continued. "Sometimes the factor in addiction might be in the genes of a grandfather or a great-grandfather. It's not the fault of a mother or a father."

Livengrin family therapist Michael Wood's seminar "Drugs and alcohol - A family problem" begins at 7:30 Tuesday night at the Lower Bucks Family YMCA, 601 S. Oxford Valley Road.