Descendants of the mutineers from the Bounty have among the lowest rates of short-sightedness in the world, scientists have found, leading to hopes they could help find a cure for the condition.
An Australian study, published in Investigative Ophthalmology and Visual Science, examined eye problems among the descendants of the sailors who settled on Pitcairn Island after the mutiny in 1789 and who moved in the 1850s to Norfolk Island. The study found rates of short-sightedness – or myopia – among the descendants of the mutineers and their Polynesian wives were half those found in the general population.
The scientists are hoping that the findings may help to discover a shared genetic coding among the Bounty descendants that could help to find a cure for myopia or to identify those most likely to develop it.
One of the researchers, Professor David Mackey, from the University of Western Australia, said the low rates among Bounty descendants were probably due to shared genetic factors, though it may also be because they spent more time outdoors. The researchers found that those whose eyes showed signs of greater exposure to sunlight were less likely to have myopia.
“We found the rate of Pitcairn group myopia is approximately one-half that of the Australian population and as a result would be ranked among one of the lowest rates in the world,” Prof Mackey told ABC Radio. “The most likely explanation is that there is a genetic difference.”
The study examined 800 of the 1,300-odd permanent residents of Norfolk Island, a small Pacific island about 1,000 miles north-east of Sydney. About half of the island’s inhabitants are descended from 12 Tahitian women, six Tahitian men and a group of nine British mutineers who set their captain William Bligh adrift in the South Pacific.
Prof Mackey said that the Bounty descendants may have a genetic predisposition towards stronger eyesight related to their shared connection to sailors who had good eyesight.
“It could actually have come from both populations,” he said. “I imagine the English sailors would have had to have very good vision, as would the Polynesian sailors. It may be that they were from populations that had low rates of myopia to start with and this has been transmitted to their descendants.”