Male relatives can confirm their biological relationship by doing a Y chromosome test. The Y chromosome is only found in males and is a sex determining chromosome.

If two males share the same Y chromosome it means that they also have the same paternal lineage.
Testing the Y chromosome can be done for the following reasons:

    • To test whether male siblings share the same biological father or other direct male biological relative. This can also be applied to genealogy and family tree research- with this test you can confirm whether you are related to someone you suspect is close relative or distant cousin.
    • In ancestry DNA testing, a paternal lineage test enables people to find out their ancient paternal ancestor, determining their regional and population affiliations.

The Y chromosome contains far fewer genes than the X chromosome. In fact it is estimated that the Y chromosome has only somewhere between 70-200 chromosomes out of the total estimated number of genes of around 25,000.

The future of the Y chromosome

Many hundreds of millennia ago, the Y and X chromosomes carried the same number of genes. Over the centuries the Y chromosome has lost the number of genes it carries. The chromosome has also shrunk considerably when compared to the Y chromosome of our ancient paternal forefathers. A Y chromosome test is extremely conclusive at determining male lineage- however, as things stand, the Y chromosome might altogether disappear one day.