DNA test may the help choose right sport

BY JACOB P.KOSHY


Does a child's chances of blossoming into an ace nter or Olympian marasprinter or Olympian mara- thon runner rest on a sliver of DNA? Sanjeev Chaudhry, the chief executive officer of Super Religare Laboratories Ltd (SRL), one of the country's largest testing laboratories, is confident it does.

In the little over three months since SRL began offer- ing its “sportsgene“ test--where for Rs2,000 lab technicians take a swab of cells from the inside of your cheeks and check for a protein called ACTN3--at least 3,000 chil- dren, Chaudhry says, across Delhi, Mumbai and Bangalore have taken the test.

The company was banking on the hype generated by the approaching Commonwealth Games and the recently con- cluded football World Cup.
“These two events contributed to a big interest among parents for getting their children test- ed. Plus it's non-invasive and not really expensive,“ Chaud- hry said in a phone interview.

According to him, the test helped parents make up their minds about investing time and money to “maximize“ their child's sporting ability.
“There's no substitute for training and nutrition, but if a particular gene helps parents nurture their children in the right sport, then it's a big ad- vantage,“ he said.

The gene in question is al- pha actinin-3 (ACTN3), which triggers the production of al- pha actinin, a protein that boosts a certain class of mus- cle fibre, called fast-twitch type 2 muscle fibre, which helps muscles generate extra force when stimulated.

According to research stud- ies, approximately three out of five people across racial cate- gories have the ACTN3 gene, which comes in two vari- ants--“R“ and “X“. Individuals inherit one copy of a variant from each parent.

While studies by Australian scientists in 2003--that first triggered substantial interest in the innocuous DNA--did suggest that of over 400 elite athletes tested, nearly 72% had at least one “R“ variant, the au- thors themselves warn against choosing a sport based on the presence of a single gene.

The “R“ variant helped gen- erate extra muscle force useful in sprints or weightlifting that require rapid bursts of power.

In his blog, Daniel MacArthur, one of the key re- searchers associated with the study said, “...Parents consid- ering using the test on their children need to be very clear about this: the test provides in- formation about only one small component of a much bigger picture. It's probably

not a great idea to base any im- portant life decisions on such limited information.“ He did not respond to a request from Mint for an interview.
MacArthur added that most studies performed so far sug- gest that ACTN3 explains just 2-3% of the variation in muscle function in the general popu- lation. The rest of the variation is determined by a wide range of genetic and environmental factors, most of which (particularly the genetic factors) were very poorly understood.

In 2007, Balraj Mittal, a ge- neticist at the Sanjay Gandhi Postgraduate Institute of Med- ical Sciences in Lucknow sam- pled 125 blood donors in Luc- know and reported in Current Science, a peer-reviewed jour- nal published by the Indian Academy of Sciences, that 52% of them had at least a single “R“, close to the average Asian population of 50% and 56% of European whites.

The scientists say they wanted to downplay the role of genes in determining athletic abilities. “If you compare Olympic medal tallies,“ Mittal said, “there's no comparing In- dians with the Europeans, Americans or the Chinese.“

Thus, training, grooming and psychological motivations were the most important fac- tors, he added. Crucially, Mit- tal and his team didn't check how the genes were distribut- ed among Indian athletes.

A slew of companies such as the US-based 23andMe Inc. and Australian Genetic Tech- nologies Ltd, among their bou- quet of genetic testing services offer to check for ACTN3, according to in- formation on their websites.
Emails to the firms went un- answered.

Chaudhry clarifies that SRL's decision to offer these tests are based on studies specifically con- ducted in India and that ACTN-3 was one of the “lead- ing factors “ in determining athletic ability.

“We submitted our research conducted in India to two journals of sports medicine and they should be in the pub- lic domain in three-six months, “he said. He added that he could share details of the sample population chosen, and other techni- cal details only after the journals pub- lished them.

Buoyed by the response to the sports gene test, SRL now plans to of- fer related tests from pinpoint- ing the genetic basis of sleep disorders as well as genetic ex- aminations to predict a child's bone strength and height.

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