Thinking about testing your DNA? Here’s what to know – Kankakee Daily Journal

During the past 20 years or so, DNA testing has become a household phrase. Television shows about tracing one's heritage and medical discoveries into the genetic links to illness have fed into this need to find one's origins or one's DNA pattern.

Now that is a possibility.

Sometimes people search their lineage out of curiosity. Family lore often carries untruths that people have believed for a few generations, and then they find out that the information was not accurate. Sometimes the curiosity stems from another desire.

"I have found that many people just want the information so that they can go on a trip and visit the geographic areas from which their ancestors came," said Marsha Peterson-Maass, a professional genealogist.

Whether it is an interest in ethnicity, lineage or medical predispositions, there is a commercial DNA test for finding out the answers.

"DNA testing technology is available for everyone, but first you need to figure out what test you want to take because there is usually a reason for why you are testing," said Peterson-Maass, during an "Understanding Commercial DNA Test Results" seminar at the Kankakee Public Library.

Peterson-Maass explained there are three different types of DNA, which include Autosomal DNA, mtDNA and Y-DNA. Each type tells something a little bit different about oneself and one's heritage.

1. Autosomal DNA offers the most extensive answers. It provides both kinship and medical results. It traces back six or possibly seven generations. Once tested, the testing company can identify other people already in its database, called cousins, who share long strings of matching DNA. (The matches are labeled cousins because somewhere back in the lineage, the two people came from a common couple pairing.)

In addition to lineage, this type of DNA also can identify physical traits and medical predispositions.

But, "I'd like to provide a word of caution here," Peterson-Maass said. "A predisposition does not mean that someone will definitely develop the condition, but if something in the report is scary, hiring a forensic genealogist through The Council for the Advancement of Forensic Genealogy to help understand the results can be a benefit."

2. mtDNA (mitochondrial DNA) offers deep ancestry information through the female line. Mitochondria are found in the cytoplasm of human cells, and while a mother passes it to every child, only daughters pass it on to the next generation. The mutation rate for mtDNA is only every 450 years or 22 generations, so having one person in a family tested is usually enough. Information found with a test for mtDNA would be able to tell a person what geographic area in which the matrilineal family line originated. It also is possible to find out what other family lines stemmed from the same origin and branched out elsewhere.

3. Y-DNA offers information passed only through males. It is the DNA on the Y-chromosome. Similar to mtDNA, Y-DNA also has a slow mutation rate. The mutation rate is about 150 to 200 years, so again, having one person tested in a family line is often enough to gather the results needed. Information about the origins of the patrilineal line can be found with a test for Y-DNA.

Commercial tests are available for each DNA type. At the moment, five companies offer commercial DNA testing: FamilyTreeDNA, DNA.Ancestry.com, 23andMe.com, Nat Geo and DNA Tribes.com. All of the companies offer some type of ethnicity report, but only 23andMe will give a chromosomal view, showing physical traits and medical predispositions.

Worried about a blood test? These testing companies use saliva samples swabbed at home and mailed in to the companies.

"It should be noted that DNA testing is not a magic solution and doesn't provide an instantaneous family tree," Peterson-Maass said. These tools work best in conjunction with traditional documentary research, she added.

It can get pricey. In general, costs for FamilyTreeDNA, DNA.Ancestry.com and 23andMe range from $59 to $99. FamilyTreeDNA offers mtDNA for $79 (for the full sequence, $199) and Y-DNA testing for $169 to $359. National Geographic offers mtDNA for $149. DNA Tribes testing starts at about $119.

And sometimes the results found can lead to further questions, as Al Mikel, a seminar attendee stated: "I just got my results from Ancestry.com, and they are something that I think I need to study."

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Thinking about testing your DNA? Here's what to know - Kankakee Daily Journal