The research was caused by the death of a six-months-old baby boy who was born with a genetic mutation. "He was born too little and too early and had a couple of wrinkles on his face. Irregularities also occurred in bone development," Karin Writzl of the institute said.

Peterlin, who compared the discovery of the gene with the discovery of a new planet, said that "now we know only 15% of the human genome". "We still don't understand the rest, why these genes are there and what significance they have for the normal functioning of a human."

The discovery will help doctors better understand ageing and enable successful diagnostics, as it will allow them to better recognise rare (genetic) diseases, Peterlin said as he presented the discovery at a news conference in Ljubljana today.

The discovery of the new gene for the appearance of a mutation has also significance for treating other illnesses, such as cancer and obesity.

The team - which fetaured the Slovenian scientists and another 12 researchers from abroad - was among the first in Europe to use a special gene sequencing technology to compare the genes of the boy and his healthy parents, Aleš Maver of the institute said.

The research discovered the same mutation in one of the three billion letters in the boy and a patient from France. The discovery of the gene was confirmed when the results were compared against other patients from Spain and Italy, he added.

The Slovenian team, which led the international research team, published the findings in the American Journal of Human Genetics.