What is DNA testing all about?
Y-Chromosome (Y-DNA) tests and mitochondrial (mtDNA) tests. A direct female line can be traced by testing mitochondrial DNA: However, since we are presently interested in tracing surnames, which are usually passed from father to son, the testing of the Y-DNA is what we are interested in. The portion of the Y-Chromosome that is tested for genealogical purposes is passed through the direct male line (from father to son) unchanged (except for an occasional mutation). Human sperm and egg cells contain 23 chromosomes. The 23rd chromosome is the one that determines a childs sex. Males have both an X and a Y 23rd chromosome. Females have two X’s and no Y’s. The human egg becomes a female embryo if the male sperm carries an X-chromosome and a male embryo when the sperm has a Y-chromosome. Fathers pass their Y-chromosomes, or “Y-DNA fingerprint, down to their sons with little, if any, variation from generation to generation. Therefore, men with identical, or near identical Y-DNA (some minor var
