… As DNA (deoxyribonucleic acid) is passed down from
one
generation to the next, some parts remain almost unchanged,
while other parts change greatly.
There is an unbreakable link between generations, however,
which is why in the past few years the use of DNA testing has
become such a popular tool in determining ancestry.
Since the Y chromosome is only passed down the male line
from
father to son, the Y chromosomal (usually referred to as Y DNA,
or Y-line DNA) is only available for males.
Tiny chemical markers on the Y chromosome create a distinctive
pattern (known as a haplotype) that distinguishes one male lineage
from another. Shared markers can
indicate relatedness between
two men, though not the exact degree of the relationship. Y
chromosome testing is most often used by individuals with the
same last name, to learn if they share a common ancestor.
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