Twins have helped Australian researchers find new genes that affect eyesight.
Stuart MacGregor from the Queensland Institute of Medical Research (QIMR) said, "Using data collected from over 1,000 sets of twins, our research has uncovered genes that affect eyesight as part of several conditions."
"We discovered a new gene for myopia (long or short sightedness), new genes affecting glaucoma risk, and a gene that causes optic nerve hypoplasia - one of the leading causes of blindness in children," he said.
The findings were part of an international study in collaboration with Professor David Mackey's research team from the Centre for Eye Research Australia.
"Identical twins are nature's clones. Despite having the same genes, the environment can make them very different. Comparing identical and non-identical twins, we can determine how much of who we are is determined by our genes and how much is influenced by environment," said MacGregor.
"Our work addresses the question of nature versus nurture. We are helping to understand how small changes in genes can have large impacts on our health.
"Large-scale genetic tests like these can increase our understanding of a range of diseases, and we need lots of twins to participate in these studies.
"The Queensland Twin Registry, QTwin recruits twins, identical and non-identical for studies like this to determine disease risk and many other factors," he said.