Do more Y-DNA STR markers improve the quality of matches’ information?

You should test more Y-chromosome DNA short tandem repeat (STR) markers when you wish to compare additional markers against others with similar results. They [...]

Don’t we all go back to Africa?

Yes. All of our Y-chromosome lineages trace back to a common ancestor who lived in Africa at least 115,000 years ago. Some lineages migrated out [...]

How does the infinite allele comparison method work for palindromic markers?

For palindromic markers, the infinite allele method counts a difference for two types of changes: a mismatch and a copy number change.

Mismatches occur when the [...]

How many generations does a Y-chromosome DNA (Y-DNA) STR test trace?

Y-chromosome DNA (Y-DNA) tests trace both recent and distant generations. The number of generations traced by a Y-chromosome DNA test depends on the type [...]

Why do I have more than one result for an STR value? What is a multi-copy STR marker?

A multi-copy STR marker is one where there are multiple versions of the same STR in different locations on the Y-chromosome. Each STR copy [...]

What is the likelihood of a non-paternal event or false paternity?

We believe that the rate of unannounced adoption or false paternity is about 1 – 3% per generation and compounds each generation. When confirming [...]