The hottest DNA test on the market, at least in my opinion is the Autosomal DNA (atDNA) test. When it was introduced it was great news for women, as either sex can take the test.
Three companies offer autosomal testing ; they are Ancestry .com, Family Tree DNA (FTDNA.com) and 23andme.com. Each company is slightly different in how they can extend your family history.
Ancestry is great if you have a well established tree on their site. One of their shortfalls is that up until recently their test was only offered in the U.S. so the matches will be primarily that. However, they are now testing in England and will in, 2015, be providing their testing in Canada and Australia. Ancestry does not provide the same genetic tools that the other companies provide.
FTDNA is a more scientific based company and you will gain a greater understanding of DNA through their site. Also they have a wider data base as they have been providing kits worldwide. Their shortfall is that their pedigree comparison tools are lacking and I don’t feel they are as user-friendly as they could be.
But back to autosomal DNA. Half of your chromosomes come from you mom and the other half from your dad so what this test does is identify your best matches among the hundreds of living relatives that have taken the test with the company you choose. Although the companies are different, each of them is testing and coming up with the same raw data, so matches are the same; First it determines how much total DNA is shared between two people. Next based on the total amount shared and the lengths of the shared segments, this determines an appropriate relationship possibility. Once you have your matches you should investigate all your 4th cousins or closer matches and compare their trees to yours.
This can be challenging; as many of the participants haven’t put up their trees. If a person hasn’t put up a tree I caution you to please be understanding. I have heard many times; “why did they do the DNA if they aren’t going to put up a tree”. It may be because they are adopted or they may have adopted parents so their really isn’t a tree that they can put up. I also think many people have gone into the field of DNA to help them push through a brick wall so sometimes we don’t know what we don’t know. Also even if a person has put up a tree it may not be extensive enough to confirm how you relate. After all, if you are 4th cousins this means you have a 3rd great grandparent in common and not everyone has that information. But it can be something you work on together. That’s why I feel it’s important to work your tree as widely as you can in both directions; not just up and down but from side to side.
Some people may not have put up a tree but have listed family names. Have a look at these and see if you can find connections. Send them messages and see if you can work together to discover how you are connected.. After all, one this is for sure…. They are your cousins.