How can DNA testing help genealogy?
For purposes of surname genealogy studies, DNA refers to the 23rd chromosome pair. Females have two x chromosomes, while males have one x and one y chromosome. The y chromosome is passed from father to son and is usually identical from father to son. Occasionally, there is a mutation. Over 1000s of years, these mutations have resulted in distinctive DNA profiles for different families. These differences are the focus of DNA testing in genealogy, often called yDNA.
