Norfolk Island: Descendants of Bounty mutiny could help prevent myopia
DESCENDANTS of the Bounty mutineers in the South Pacific have better eyesight than average, according to scientists who hope to identify the genes responsible for short-sightedness. Their research might one day allow doctors to advise those at risk of myopia to take preventative measures.
Scientists studied the inhabitants of Norfolk Island, almost half of whom are descendants of nine British sailors from HMS Bounty and their Tahitian wives who moved there from Pitcairn Island after the infamous mutiny in 1789.
They found that Norfolk Islanders with Pitcairn ancestry have a rate of myopia approximately half that of the Australian population, ABC radio reports.
Because myopia is known to have environmental as well as genetic causes – for example, spending too little time outdoors can increase the risk – the researchers needed to eliminate the possibility that their findings were simply down to Pitcairn islanders spending more time in the sun.
Led by Professor David Mackey of the Lions Eye Institute in Perth, they came up with a clever way of determining how long each participant in the study had spent outdoors, based on the extent to which they had developed a condition known as ‘surfer’s eye‘.
The researchers found using this measure that there was no significant difference between the amount of time Pitcairn descendants and other Norfolk Islanders spent outdoors, meaning the genetic effect is real.
Mackey says his research could help prevent the development of myopia in some people. “With any disease that involves genes and environment, you can identify the people who are at high genetic risk, and intervene by reducing the environmental risk,” he explains.
People with “high risk” genes would be advised to “get outdoors more in their teenage years to reduce their chances of myopia”.
As to why Bounty mutineers should have such good eyesight, Mackey explains to The Daily Telegraph that the genes might come from both the British sailors and their Tahitian wives. “I imagine the English sailors would have had to have very good vision, as would the Polynesian sailors.”
- Eye Eye captain: Bounty mutineer descendants may hold key to myopia (dailystar.com.lb)
- Surprise Bounty: Mutineers’ descendants have lowest rate of short-sightedness ever found – and their DNA could hold key to cure (dailymail.co.uk)
- How an 18th-Century Mutiny May Help Explain Migraine Headaches (mentalfloss.com)