There are three basic types of DNA testing:
Autosomal DNA (atDNA)
These tests are offered by AncestryDNA, MyHeritage, Family Tree DNA, 23andMe, and LivingDNA. This is the primary type of test for women and men to take when searching. atDNA tests examine ~700,000+ markers on your 22 pairs of chromosomes plus your X chromosome(s) on some tests.
Y-DNA testing is offered by Family Tree DNA (FTDNA). It is for men only. It may be helpful to identify a surname. Talk to us about your goals before deciding to purchase this test. It gives information on the partrilinial line – your father’s father’s father’s father’s father’s…father.
Mitochondrial DNA (mtDNA).
This test rarely provides help to searchers. Talk to us about your goals before deciding to purchase this test. It is offered by FTDNA. This test is for women and men. It gives information on the matralinial line – your mother’s mother’s mother’s mother’s mother’s mother’s…mother. This is not the X chromosome. Your mtDNA haplogroup is provided as part of a 23andMe and LivingDNA DNA test. mtDNA Matching is not provided by either company.
The tests you can get from drug stores or from other companies are not reliable as they only measure a 20 ~ 30 SNPs compared to 700,000+ SNPs measured by an genealogical test. They can also be even more expensive, running several hundreds of dollars. In addition, the results from them and forensic type tests are not comparable.
If You have Known Biological Family
If you have known living biological relatives (such as you know your mother, but not your father, or a half sibling) additional DNA tests should be done on those biological family members to help separate DNA matches from the sides you know from the sides you don’t.