Last month I did the Heritage DNA , because of one of my cousins did the test ,but hers was done by Ancestry ,I was very surprise by the result , we have nothing in commune , i was very concert concern with my result , just because it shows nothing from my family side, supposedly I’m 79.7 % Central American , 13.9% Iberian and 6.4 Scandinavian My whole family is from South America ,so why 79.9 Central American ,any way I was so intrigue that I did the Ancestry Test now , I’m waiting for the result and I’m dying to see the results
There are a number of reasons why the vast majority of living humans are a blend of ethnicities. Firstly, from around 1850 onwards, people started to migrate around the world and mix in large numbers. Secondly, as national borders have changed over time, the only clear cut ethnic groups are those that are highly isolated. For example, as individuals have migrated in large numbers between France and Britain in the last few thousand years; those in Northern France exhibit a similar ethnic mix to those in Southern England.
For these reasons, mapping segments of your autosomal DNA to whole continents can be determined with a high level of certainty, but when you try to attribute these segments to specific tribes, regions or even countries, the certainty decreases. This is why some genetic ancestry companies will attribute a proportion of your DNA to areas such as ‘Eastern Europe’ or ‘Southern Asia’, instead of to specific countries.
In the case of a great-grandchild, or a great-great-grandchild, something even stranger can happen.  Remember that a child will get half of their mother’s DNA, but there is never ever guarantee which 50%.  The way it is chosen is fairly random, as far as scientists know.  Take the example of the 100% Eastern European person.  Their great-grandchild will inherit 50% of their DNA from their part-Eastern European parent, but there is a good chance that they won’t inherit all of the Eastern European DNA that they could potentially inherit.  It’s possible for a person to share NO DNA with a great-great grandparent, even though there is a verified genealogical relationship.
Next, you'll receive an email alert that your results are ready, and that's when the fun begins. Your results may not be as dramatic as those portrayed in TV ads, but you may find some surprises. One important note: Results are different for women and men. Women, who have the XX chromosome, can only trace back the maternal line. Men, having the XY chromosome, can track back the maternal and paternal line, painting a complete picture. If you're a woman, it's worth asking your brother, if you have one, to take a test and share the results. When some of these services ask for your sex when you order your kit, they simply want to know about your chromosomes.
— Once you have chosen a test and received your autosomal results there is still a great deal more fun to be had. Independent tools and websites created by scientists and enthusiasts allow you to take the raw data provided from FTDNA, 23andMe and Ancestry DNA and explore them in astounding detail–giving you a wide variety of new admixtures, phasing options, chromosome browsers, SNP tools and connections with family across the world. Gedmatch is our favorite because they have so many wonderful and meticulously updated tools from a variety of sources. Easily upload your raw data and run your results for free (if you love the tools, don’t forget to donate and uncover even more options.)