___ asked:

In doing some recent Y-DNA studies, I find that the Spanish forefathers to Mexicans and White Americans share a common R1b1 Celtic ancestor. Mexican surnamed men and Anglos share common ancestry. Is this immigration issue pointless? Is it infighting? Your thoughts?

Rich Fuller asked:


DNA tests are becoming more and more popular but should you have a DNA test? Before deciding to have a DNA test there are a number of things you need to consider. In this article we will be discussing some things you should consider before having a paternity test, an ancestry DNA test or similar DNA tests.

Firstly, if you are considering a paternity DNA test, think first about the situation at the moment; how old is the child now and what is your current relationship to the child? If the child has not yet been born is a newborn baby and you have not yet been able to bond with the child because of uncertainty as to whether you are the father or not then having a paternity DNA test may be the solution for you and these tests can help cement family relationships that are not yet established by confirming who the father is. If, however, the child is older and you have already formed a relationship with the child as its father then paternity DNA testing can actually have negative consequences; what happens if you suddenly discover you are not the father? How will this affect your future relationship with the child? You will need to think through these issues carefully before deciding to go for a paternity DNA test.

These factors also need to come into consideration if you are testing for other family relationships - for example grandparent DNA tests, sibling DNA tests, etc. No matter what the relationship it is important to consider where the relationship is at currently and how you expect the DNA test to change the relationship. It can be an extremely traumatic experience to discover that what you thought was the relationship between you and someone is actually not the case. Visit http://www.geneticdnatestinghelp.org for more information on DNA testing.

What about genealogical and ancestry DNA tests? If you are considering going for an ancestry DNA test you should think about how the results could influence your life as well and how you would feel about obtaining different results. In one case someone who thought they were African American discovered that they actually had no African blood in them but a mixture of other races. Having lived their whole life as an African American this presented many problems - who were they really and how were they going to react to this sudden change in their identity? These are questions that you need to consider when considering going for an ancestry DNA test is how it could change your identity.

DNA tests can be very useful and informing, they have many benefits and in certain circumstances can bring families closer together, help build a family tree or contribute to our lives in other ways; but DNA tests can also be destructive and it is important when considering whether to have a DNA test that you take these factors into consideration.



Ancestry.com DNA testing

Alex Blake asked:

DNA testing is done for many different reasons. DNA evidence can link an alleged criminal to a crime scene. DNA paternity and maternity testing can identify a child's father or mother. DNA relationship testing can determine if two individuals are full or half siblings. DNA ancestry testing can determine ethnic origins and genealogical roots.

How DNA testing is done depends on the results desired and the samples available. DNA fingerprinting (or profiling as it's also known) is the process of analyzing and comparing two DNA samples. Only identical twins have the exact same DNA sequence, everyone else's DNA is unique. This makes DNA the perfect way to link individuals to each other or to locations where they have been.

The entire DNA chain is incredibly long, much to long to examine all of it. Human DNA is made up of about 3.3 billion base pairs. The differences between DNA samples occur only in small segments of the DNA--the rest of the DNA is pretty much the same. DNA testing focuses on those segments that are known to differ from person to person.

As DNA testing has evolved over time, the testing methods have become more precise and are able to work with much smaller DNA samples. Early DNA testing was done using dime-size drops of blood. Today's tests can extract DNA from the back of a licked stamp. The DNA must be extracted from whatever sample is provided. DNA must be isolated and purified before it can be compared. In essence, it has to be "unlocked" from the cell in which it exists. The cell walls are usually dissolved with a detergent. Proteins in the cell are digested by enzymes. After this process, the DNA is purified, concentrated, and tested.

DNA testing is done most often today using a process called "short tandem repeats," or STR. Human DNA has several regions of repeated sequences. These regions are found in the same place on the DNA chain, but the repeated sequences are different for each individual. The "short" tandem repeats (repeated sequences of two to five base pairs in length) have been proven to provide excellent DNA profiling results. STR is highly accurate--the chance of misidentification being one in several billion.

Ancestry.com DNA testing