Which companies offer genealogy DNA testing services?

Answer 1

There are several DNA tests that can be used to explore your genealogy. For example, there are Y-DNA tests which test the Y chromosome found only in males. There are also mtDNA tests which examine the mitochondrial DNA, a small circle of DNA that we inherit only from our mothers. And there are autosomal DNA tests, which examine the DNA of your 23 chromosomes. The cost of these tests has come down considerably in the last few years.

There is much more information about the different types of tests, and the different testing companies, at the International Society of Genetic Genealogy ("ISOGG") wiki located at http://www.isogg.org/wiki.

Answer 2

Commerical genetic genealogy tests (which use DNA collected from saliva or cheek swabs instead of blood) have many uses, including to support a known genealogy or to build an unknown genealogy. For example, a Y-DNA test can be used to support or deny a hypothetical relationship between two male lines. And autosomal DNA can be used to explore many different lines.

Rarely, however, can DNA alone "prove" a family tree or genealogy. Instead, DNA always works best when combined with traditional genealogical research.

Answer 3

DNA testing is used in testing ancestry by comparing the DNA of ancestors with that of their descendants. Since genetic material is inherited from one's ancestors, descendants are likely to share more genetic material with their ancestors than with those to whom they are not related.

Answer 4

This can be problematic, as the tracers run through the male genome, so if it's by way of your mother or grandmother, than you're out of luck.

Answer 5

There are several companies which offer genealogy DNA testing services. Some of these companies include Ancestry DNA, DNA Consulting, Family Tree DNA and Oxford Ancestors.