Daddy's Genes

The Invisible Inheritance

By Johnathon Allen

Whether dads want to or not, they give their children far more than just a last name and an inheritance. In fact, a father's genetic legacy may be the most significant contribution they'll make to their children's lives.

Along with sur names and savings accounts, fathers supply their progeny with half of the genes that serve as the chemical blueprint for creating every cell in the human body. Scientists have known for years that this genetic code is responsible for determining the physical traits of a couple's offspring (size, shape, hair color, eye color, etc.), but recent studies indicate that "genetic programming" is also responsible for more subtle characteristics such as predisposition to diseases, propensity for weight-gain, alcoholism and a person's relative intelligence.

The details regarding exactly how these genetic traits are passed on, and which parent passes on what traits, still presents a considerable mystery to researchers. Though, hopefully, not for long. The Human Genome Project, an international scientific effort to catalog the 3.3 billion pairs of chemical combinations that constitute human development, is nearing completion. Once this previously unfathomable undertaking is realized, scientists will begin to clearly understand the subtle complex genetic forces that make us who we are. In the meantime, current research suggests that dads (and moms for that matter) have a particular influence over certain characteristics passed onto their kids.

Because both parents contribute exactly one half of their child's genetic makeup, it was long thought that both parents had equal input, but the discovery in 1984 of genomic imprinting revealed that sometimes only one parent gets a say in particular traits.

"Genes exist in pairs, one from the mother and one from the father," says Dr. Stephen Hall, a genetic researcher at Baylor College of Medicine in Houston, Texas

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