DNA Basics: What DNA Testing
Can Do for You

Everyone has DNA. But most people don't understand the DNA basics.

While your DNA is different than mine, it is much like that of your parents and other people in your family tree. That makes DNA ideal for relationship testing of two presumed relatives.

The classic relationship test is a DNA paternity test, such as EasyDNA.

Comparing a child’s DNA with a suspected father can determine—without any doubt—if that man fathered the child.

Today, DNA can also confirm other relationships, like siblings, half siblings, grandparent and grandchild, and aunt/uncle with nephew/niece. The more distant the relationship the less DNA you have in common. But you can detect many distant cousins. Those are DNA basics.

DNA Basics: Testing Yourself

There are large and growing databases of people who have already taken the most popular tests. By testing yourself, you will learn who you match. Over time, you will see additional matches as more people get tested.

Combining family tree information from your matches with what the DNA says about your relationship is what leads to new discoveries in YOUR family tree. For example:

  • Genealogists are using DNA tests to get around their “brick walls” where the paper trail ends.
  • Adoptees are overcoming family secrets, sealed records and even outright lies to discover and reunite with their biological families.
  • People curious about their ethnic ancestry are learning what parts of the world their ancestors came from.
  • Adults who discover or suspect that the man who raised them was not their biological father are identifying previously unknown fathers.
  • Children of sperm and egg donors are testing their DNA to find biological parents and siblings.

Testing additional family members from different branches of your family tree can provide even more information when you see which matches you have in common or not in common.

DNA Basics: How Do I Get Tested?

It’s easy. You order a test from the company’s website. They ship a home test kit to your address. You collect a sample of your DNA and send it back. 

They analyze your DNA and compare it to every other person who has taken the same test. They notify you by email when your results are ready. Then you log into your private, password protected account to see your results.

Collecting your DNA sample is easy and painless with my recommended DNA testing companies.

AncestryDNA and 23andMe use a “spit kit” where you simply collect some saliva in a tube.

Family Tree DNA, MyHeritage DNA, and Living DNA use test kits that include swabs for lightly scraping cells from inside your cheeks. Either method is generally effective.

Subjects who are very young or very old may have difficulty producing a lot of saliva or spitting into a tube. For them the cheek swabs will be easier to use.

NOTE: A mortician can use cheek swabs to collect DNA from the recently deceased, though I recommend you don’t wait that long.

DNA Basics: Three DNA Test Types

The three DNA tests used in genetic genealogy are Autosomal DNA, Y-DNA, and mitochondrial DNA.



› DNA Basics


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