London: Scientists have claimed that a rare and striking plant native to Japan `Paris Japonica` has the largest genome ever discovered.
The vast range of DNA in plants and animals has long fascinated and puzzled researchers. Now, a team at Kew Gardens in London says the ordinary-looking white flower has a genetic code 50 times longer than that of a human being.
"We were astounded really. Some people may wonder what the consequences are of such a large genome and whether it really matters if one organism has more DNA than another," The answer to this is a resounding `yes`. "Having a large genome increases the risk of extinction. The larger it is, the more at risk you are," said Ilia Leitch, the lead scientist.
In fact, with 152.23 picograms of DNA, the Paris japonica has around 15 per cent more than the previous record holder, a long-bodied muck dweller known as marbled lungfish,
with 132.83 pg.
The plant is also more than 50 times bigger than the human genome, which has about 3 million bases and measures about 6 feet in length.
According to the scientists, the importance of size lies in the fact that the more DNA there is in a genome, the longer it takes for a cell to copy all of its DNA and divide.
"The knock-on effect of this is that it can take longer for an organism with a larger genome to complete its life cycle than one with a small genome," the British media
quoted Leitch as saying.
The findings have been published in the `Botanical Journal of the Linnean Society`.