A support group for unmarried parents and their children has called for the right of all children to have their paternity established.
In an information leaflet launched today, Treoir said that children of parents who were not married have no automatic right to have their paternity established.
It says children have a right to a name and an identity under the UN Convention on the Rights of the Child.
Treoir chairwoman Eilis Walsh stated: "It is really important for, and indeed a basic right of all children to know who they are and where they come from.
This Information Leaflet outlines the various ways in which paternity can be established and includes information on the DNA testing procedure".
The leaflet entitled Establishing Paternity provides a list of contacts where DNA samples can be brought for testing abroad.
It also warns against using unauthorised agencies for testing DNA samples as these results may not be considered reliable for court procedures.
"In addition, unregulated agencies may be willing to undertake paternity testing without a mother's consent. This could be seen as unethical and illegal," the leaflet warns.