New Delhi: Scientists hope to genetically tweak ordinary oranges into `healthier` blood oranges, which could combat obesity and heart disease.
They have identified the `ruby` gene that makes the blood orange red.
The distinctive red pigment is believed to have health benefits, which include combating obesity and heart disease.
They also discovered how the gene is activated, raising the possibility of switching it on in ordinary `blond` orange varieties, the Daily Mail reported.
One recent study found that drinking blood orange juice with a full English breakfast reduced the harmful effects of a fat-laden fry-up.
Blood oranges need a period of cold as they ripen and currently the only place where they can be reliably grown on a commercial scale is in the foothills of Mount Etna in Sicily in the Mediterranean.
As a result, blood orange juice is hard to come by and a carton costs about 1pounds more than ordinary orange juice.
"Blood oranges contain naturally occurring pigments associated with improved cardiovascular health, controlling diabetes and reducing obesity," said Professor Cathie Martin, who led the research team from the John Innes Centre in Norwich.
"Our improved understanding of this trait could offer relatively straightforward solutions to growing blood oranges reliably in warmer climates through genetic engineering," she stated.
The pigments are anthocyanins, chemicals that colour red, purple and blue fruits.
In 2010 a study found that blood orange juice protected laboratory mice on a high-fat diet from obesity, according to Prof Martin.
The mice developed 30 percent less white fat than animals given water or ordinary orange juice.
A recent, as yet unpublished Italian study from the Catholic University of the Sacred Heart in Campobasso looked at the breakfast-enhancing qualities of blood orange juice.
Volunteers were asked to eat a hearty full-English fried breakfast, high in saturated fat. Those who accompanied it with half a litre of blood orange juice were less at risk from blood clotting three hours later, said Prof Martin.
Arterial stiffness and levels of harmful triglyceride blood fats were also reduced.
The effects were most pronounced in the unhealthiest participants. A test batch of genetically created blood oranges is currently being grown in Valencia, Spain.
"Hopefully in the near future, seven years down the line, we will have blood orange varieties which can be grown in the major orange growing areas like Brazil and Florida. So blood orange juice will become more available worldwide and the healthy properties enjoyed by more and more people," Prof Martin said at a press conference in London.
The study has been published in The Plant Cell journal.