How many DNA testing companies will show you how to interpret DNA test results for family history or direct you to instructional materials after you have had your DNA tested? Choose a company based on previous customer satisfaction, number of markers tested, and whether the company gives you choices of how many markers you want, various ethnic and geographic databases, and surname projects based on DNA-driven genealogy. Before you select a company to test your DNA, find out how many genetic markers will be tested. For the maternal line, 400 base pairs of sequences are the minimum. For the paternal line (men only) 37 markers are great, but 25 markers also should be useful. Some companies offer a 12-marker test for surname genealogy groups at a special price. When you order a home testing kit, you'll get mouthwash or a felt tip to rub inside your cheek and mail back. Find out how long the turnaround time is for waiting to receive your results. What is the reputation of the company? Do they have a contract with a university lab or a private lab? Who does the testing and who is the chief geneticist at their laboratory? What research articles, if any, has that scientist written or what research studies on DNA have been performed by the person in charge of the DNA testing at the laboratory? Who owns the DNA business that contracts with the lab? How involved in genealogy-related DNA projects and databases or services is the owner?