DNA 

The following is a selection of sources for DNA related research.

Ancestry.com is one of the key DNA sample sites with the largest data base of likely matches

FindmyPast has a strong British focus but is also an excellent choice

23andMe is also a DNA site with a stronger focus on health issues than on genealogy.

DNA Explained is a comprehensive blog discussing using DNA for your research

DNA Painter is an award winner website to help you demystify your DNA results.

Family Tree DNA

GEDmatch provides more applications for comparing your DNA test results with the most people worldwide. 

The International Society of Genetic Genealogy (ISOGG) advocates for and educate about the use of genetics as a tool for genealogical research, and to promote a supportive network for genetic genealogists. 

PBS's Your DNA Guide is a good source of information on your DNA results.