By Dr. Brian McDonough

There is a reason we look a lot like our mom and dad. Physical traits like nose length, eye color, and hair type, are passed on from parents to children. We know that they are genetically determined.

Of course what we don’t always know is which genes are responsible for them. And there is a good reason for that — some traits are regulated by more than one gene, and these are known as polygenic, or complex traits.

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The best example of a complex trait is a person’s height. But genetic research is improving every day thanks to shared research.

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Scientists from over 300 labs throughout the world combined their data and have found that by screening the genes of over 180,000 people for height-associated differences in the DNA sequence, there are 180 genetic markers associated with height.

Sounds hard to study but they also found that these genes are grouped together according to distinct functions. Again, not simple but we are way ahead of where we were just ten years ago.

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Reported By: Dr. Brian McDonough, KYW Newsradio Medical Editor