8 Common DNA Questions and Answers

DNA has been used to identify people since the 1980s, and since that time scientists have learned how to use DNA to not only identify certain traits in a person, but also to make accurate, educated assumptions about a person’s future as far as certain health conditions are concerned. DNA is a fascinating thing, but it can be complex to understand.

1. What determines your DNA?

A person’s DNA is determined at conception and, most simply put, is made up half of the mother’s DNA and half of the father’s. This is why DNA testing can help determine if someone is a blood relative – like a mother, father, or sibling – because many elements of the DNA will match.

2. Where is DNA found?

Every part of your body contains DNA. Your saliva, blood, and even your hair contain your DNA, and can all be used to confirm a match. Blood is often considered the best source of DNA, however saliva is also used very frequently, especially recently with the emergence of home testing DNA kits.

3. Is it Effective?

If done properly, using saliva for DNA testing is considered equally as effective as using blood. The only concern is if the saliva sits for too long and isn’t stored properly, the cells can break down and will no longer be effective for testing.

4. What does DNA tell us?

DNA can identify a person. For instance, to confirm if two people are related. It can also indicate where someone’s ancestry may lie, even if their ancestry is a combination of many different ethnicities, it can be broken down in DNA testing to give that person a good idea of where they come from. It can indicate some visual aspects of a person – like hair colour or eye colour – and it can also indicate what health issues that person may experience later in life, for example certain types of cancer.

5. What kinds of DNA tests are there?

Basically, there are three distinct types of DNA tests. A Y-DNA test can only be taken by men, and it tests the Y-chromosome. As women do not have a Y-chromosome, they cannot do this type of DNA test. This type of test can be used to explore only the patrilineal line. An mitochondrial DNA test or mtDNA test can be taken by both men and women, and tests the matrilineal side of the family. Finally, the autosomal test can also be taken by both men and women and it tests the DNA more broadly. This means it can indicate connections on both the matrilineal and patrilineal lines.

6. How reliable is DNA testing?

DNA testing is very accurate. While it can never be confirmed to be 100 per cent accurate, it is still very reliable. When it comes to direct relatives, DNA testing is 99.9 per cent positive.

7. What about genealogical testing?

When it comes to genealogical testing, it is still very accurate but in a different way. This type of testing indicates where DNA similar to that is found in the world, and so requires more educated guessing and analysis to really mean anything.

8. Are there drawbacks to DNA testing?

Many people just want to find out what their genetic makeup looks like – it is a very interesting way to learn more about yourself. However, some people are not prepared for the surprises a DNA test can give. There are many cases where DNA tests provide news that people just don’t want to hear, like that the person’s parents weren’t their real parents, or that they carry a genetic disorder. However, these negatives can be turned into positives as well, it all depends on your point of view.