Story URL: http://news.medill.northwestern.edu/chicago/news.aspx?id=181415
Story Retrieval Date: 12/9/2013 2:01:29 PM CST
Courtesy Megan Smolenyak Smolenyak
A man's patrilineal ancestry (a father’s father’s father, and down the line) can be traced using the DNA on his Y chromosome. Because the Y chromosome is passed down almost unchanged from father to son, the test results from two men can be compared to determine if they share a common ancestor.
Because only males have Y chromosomes, women who want to determine their direct paternal DNA ancestry can ask someone in their family who shares a common patrilineal ancestry with them – a father, brother, paternal uncle, etc. -- to take a test for them.
Mitochondrial DNA testing
Mothers pass their mitochondrial DNA to all of their children, so women and men alike can have their mitochondrial DNA tested to find out information about their matrilineal ancestry. If there’s not a perfect matrilineal match, this type of testing can be less accurate than Y DNA testing.
Autosomal DNA testing
As genealogist Megan Smolenyak Smolenyak, puts it, this kind of testing is noteworthy because it “frees us from the tyranny of direct gender lines” and can determine the degree of relationship between any two people. The closer the relationship, the more accurate it is. When you find a match, you use conventional genealogy to figure out from which branch of your family tree that cousin might come.