How Reliable Is The Dna Testing Offered By Sites Like Ancestry.Com Or 23andme? I'm Skeptical About The Reliability Of A List Of "cousins" Based Strictly On Dna, Since I Always Hear That We Share 90+% Of Our Dna With Chimps And Palm Trees.


I was always interested in finding out if I have any cousins that no one in my family know they exist by taking a DNA test. But I also read an article that a major portion of human DNA is common with palm trees and chips, which made me wonder if these DNA tests are reliable.


You may already know that there are 46 chromosomes which are found in pairs. 23 of them come from your father, while the remaining comes from your mother. When you were born, your reproductive cells will have 23 chromosomes, out which 22 are known as autosomes, while the last one is an allosome. If you are a male, the allosome will be the “X or Y” chromosome, which determines the sex of your children. If you are a female, the allosome will be “X” chromosome.

Theoretically, 50% of your chromosomes come from your mother, while the remaining is from your father. However, in reality, this is not always the case as one chromosome only represents your father, due to which, your mother’s chromosome gets lost during the process fo recombination. Due to this, it isn’t always necessary for your ancestors and their descendants to inherit the same DNA. As a result of this, there is a chance that you will have genealogical cousins, but they are not your genetic relatives.

Companies such as 23andMe and Ancestry will only check those portions of the genome which will change. I find this practice good for approximation, but you don’t always get perfect answers.

I would like to give you a personal example to show you that DNA testing from these companies is reliable. I have been doing my research on my family history for several years. I have discovered several cousins along with the distant ones. To ensure that my research is accurate, I asked my cousins to take the DNA tests. The results were quite accurate, as the tests said they were my cousins. I even got to know about cousins I never even knew existed, thanks to Ancestry. Again, I would like to point out that there were minor errors in the test results, as some of my second cousins came under the third cousin’s category.

I also have a story of my friend who took the DNA test from 23andMe. A lot of his second, third, and fourth cousins from the test results was on point. If you think about it, there is no way 23andMe could have faked these test results.

Again, it is important to know that these DNA test results may not work for everyone. For example, if you are from North America or Northern/Western European countries, the chances of finding ancestors is higher, as companies have a large database on these regions. However, people from other areas may not be successful in their search for ancestors, due to the lack of data.