Molecular Biology

Dna and its Relationship to Family History

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"Dna and its Relationship to Family History"
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Why bother with Y-DNA or mt-DNA tests?

Did you ever get to the point where you checked all the records you could find but could not determine where your family Surname originated? If you have found gaps, then the next step may be a Y-DNA or mt-DNA test.

The Y-DNA test can allow a male to compare his DNA or a male relative (for a female) to others people's Y-DNA with the same surname. The person can even compare the data with those of different surnames who may be related to them in some way.

There is a case where a family rumor causes someone to doubt their great-great-great grandpa was really the father of their great-great-great grandma's child. This gives a person some basis to test.

In a Surname studies the results of a Y-DNA test may give a person the answer whether their Irish relative whose data was allegedly swept overboard, was from County Cavan or County Claire based on the DNA. This can fill in the gaps where there are no censuses to check or passenger records are too numerous to rule down which John Smith the person is descended from.

The results can be compared to others who want to know where their relatives moved to in the United States. The testing companies give you the data so you can check blogs, websites, and other sources and can also put the relatives in touch with them if they allow them.

Why mt-DNA test? This test is for determining which group of women the female ancestor's line came from. A person may be able to trace a family back to 1200 by records from the local church but with mt-DNA they may be able to check back to an Ice Age! Since after the plagues, ice ages, and other catastrophic events there were fewer women to give birth, these women would have the descendants around today, in theory.

The mitrochondrial DNA is tested and interpreted. The results can be checked against other people who took the test. It can even determine the likelihood of being from one of the females who may be from a very different area than they would guess. I am checking one relative for possible Jewish ancestry based on the fact people have said he looks Jewish. My data search came up with a possibility on his great-great-great grandma's side. I am anxious to find out the results of this test.

Sometimes it is a good idea to take the test just to see if anyone matches you. Some of us feel like no one could possibly be anything like us. The DNA tests could prove us wrong.

If the test doesn't give us the results we are looking for, the data may open our minds to new places to look so we can do more paper research. DNA breaks brick walls.

More about this author: Rosanne O'Reilly

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