Y chromosome (Y-DNA) testing A man's paternal ancestry can be
traced using the DNA on his Y chromosome (Y-DNA). This is
particularly useful because the Y chromosome, like many European
surnames, passes from father to son, and can be used to help
study surnames. Women who wish to determine their paternal
ancestry can ask their father, brother, paternal uncle, paternal
grandfather, or a cousin who shares the same paternal lineage to
take a test for them (i.e. any male family member who has the
same surname as her father). What gets tested Y-DNA testing
involves looking at segments of DNA on the Y chromosome (found
only in males) where sequences of nucleotides repeat, known as
short tandem repeats (STRs). These segments are considered
"junk" DNA. The segments which are examined are referred to as
genetic markers and are designated by a DYS number (DNA
Y-chromosome Segment number). These STRs may also indicate a
likely haplogroup for the Y chromosome, though this can only be
confirmed by specifically testing for