London, Feb 14 (IANS) A specific gene that plays a crucial role in ensuring DNA is copied correctly when cells divide and grow can cause growth defects associated with a rare type of dwarfism, says a study.

"This research sheds new light on the mechanisms underlying DNA replication, and the effect on human health when this process goes wrong," said Grant Stewart from University of Birmingham in Britain.

During the study, published today in Nature Genetics, the researchers looked at genetic information from more than 250 people around the world with microcephalic dwarfism, a group of disorders characterised by short stature and reduced head size.

They found that 29 of the individuals had faulty versions of a gene called DONSON.

Tests on cells growing in the laboratory revealed that this gene plays a crucial role in ensuring DNA is copied correctly when cells divide and grow.

Cells from patients with mutations in the DONSON gene had difficulty in efficiently replicating their DNA and protecting it from uncontrolled damage, ultimately leading to the growth defects typical of microcephalic dwarfism.

This research raises the potential of more accurate diagnoses for patients with genetic microcephaly, in addition to providing an insight into how similar rare hereditary diseases are caused.