Our Y-DNA STR tests use a technique called polymerase chain reaction (PCR) to examine a defined set of STR markers in your Y-DNA. This technique determines the number of repeats at each marker tested - either 20, 44 or 101 markers, depending on the requested analysis. When two individuals take the Y-DNA STR marker test, their STR numbers can be compared to see if there is a match. The confidence with which the Y-DNA STR test can predict a relationship between two individuals increases as more STR markers are tested. A calculation called “TMRCA” (time to most recent common ancestor) can be performed to estimate how many generations ago the two males likely shared a common paternal ancestor. Comparing more Y-DNA STR markers will provide a higher stringency comparison and a more precise TMRCA calculation.
Y-DNA STR tests can be used for forensic applications, investigating relationships, tracing distant male relatives who may have descended from the same paternal lineage and identifying links to famous people. It is a simple test that can provide you with rich information about your paternal lineage.