http://familydoctor.org/familydoctor/en/prevention-wellness/staying-healthy/healthy-living/genetic-testing-what-you-should-know.printerview.html
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American Academy of Family Physicians
Some genetic abnormalities, or “gene mutations,” may run in families. Find out the pros and cons of being tested for genetic diseases that might run in your family. A sample of blood or skin is usually needed for genetic testing.