A letter was published in the medical journal Lancet on Friday in which Arthur Beaudet of Baylor College of Medicine in Houston revealed that DNA experts might come across some thorny issues while performing genetic tests on children with developmental or intellectual problems.

Dreading about possible ethical dilemmas, he said that experts studied the DNA of disabled children to understand the nature of their disorders but in the process they could identify the children as having been conceived by two close relatives.

Legally an expert is supposed to inform his/her authorities in case the mother conceived as a minor. They believe that anyone who comes across such finding ought to report it to child protection services and the police.

These types of DNA tests are often used to generate the evidence in the cases of incest. Without saying anything about the prevalence of the issue, Beaudet and his colleagues gave suggestions about forming committees to discuss the legal and ethical issues surrounding DNA testing.

"I am absolutely certain this will be a big issue going forward," said Ross Upshur, Director of the Centre for Bioethics at the University of Toronto. He was not connected to the letter. "Science is moving so fast it is often discovering information that we won't know is sensitive until the future," he said.