More men to torment: Mallika Sherawat and Ranvir Shourey in a scene from the movie Ugly Aur Pagli

New Delhi, Sept. 28: Better start perfecting that 99-slap-one-kiss regimen all over again, Pagli. Uglys are going to be around for another 300 million years for you to torment.

Men are in no danger of extinction from a dying Y chromosome, new research has indicated, junking earlier predictions that the sex chromosome will lose all its genes and wipe out all males.

A study conducted by a US-based biologist and presented today at a human genome science meeting in Hyderabad shows that the human Y chromosome will retain its genes for at least another 300 million years.

The findings contradict recent predictions by some leading biologists that the Y chromosome — which has lost most of its genes over time — will lose its last gene within the next 125,000 years to 10 million years.

“There could be a million other reasons for an extinction, but men won’t go extinct because of gene loss on Y,” Doris Bachtrog from the University of California, San Diego, told The Telegraph, shortly before presenting her findings.

It may not be good news for those who blame men for all the evils of the world. But for those like Kuhu, played by Mallika Sherawat in the recent movie Ugly Aur Pagli where she orders her boyfriend Kabir (Ranvir Shourey) around and gives him several slaps and one kiss, the research findings ensure an uninterrupted supply of boys to twist round their little finger.

Scientists believe a pair of identical chromosomes diverged into the X and Y sex chromosomes between 300 million and 150 million years ago. The mammalian Y chromosome is a unique piece of genetic architecture primarily responsible for determining gender through a gene called SRY which makes males (XY). Without Y, mammalian embryos are — by default — female (XX).

Several earlier studies had shown that the Y chromosome has lost most of its genes. About 150 million years ago, biologists believe, Y had more than 1,000 genes. It now has only between 30 and 50 functional genes.

Geneticist Jennifer Graves at the Australian National University is among biologists who have been arguing that the progressive degeneration of the Y chromosome may cause it to disappear entirely within the next five million years.

But Bachtrog’s new study has shown that the rate at which Y is losing genes has slowed down over time. Her research suggests that most of the loss of genes on Y occurred within the first 50 million years of its existence.

“The loss of genes from Y has become exceedingly slow,” Bachtrog said. “At the current rate of its degeneration, the human Y would still have 20 genes left after another 300 million years,” she said.

Bachtrog has developed a mathematical model to analyse how the Y chromosome will behave over time, taking into account how mutations, random effects and other evolutionary factors would influence the loss of its genes.

“I don’t think the controversy over the fate of the Y chromosome is going to go away,” said K. Thangaraj, a scientist at the Centre for Cellular and Molecular Biology, Hyderabad, who chaired the session where Bachtrog presented her research.

“It’s a unique chromosome that has lost more than 90 per cent of its genes — and we know that it is not essential for survival,” Thangaraj told The Telegraph. “Without a Y chromosome, there’s no deleterious effect. An individual can be perfectly healthy.”

But even Graves believes gene loss on Y won’t mean the end of males. “If humans haven’t gone extinct by then, new sex-determining genes and chromosomes will evolve, perhaps leading to a new hominid species,” she once said.