New Delhi: India's parliament is becoming a closed shop with most young lawmakers drawn from established political families, a British author has said in a new book that is making waves in New Delhi.

Patrick French, a London-based writer who is married to an Indian, conducted the first ever analysis of all 545 members of the Lok Sabha (lower house), and discovered dynastic families now exert an extraordinary grip on power.

Despite massive social upheaval in India over the last 20 years, more than two-thirds of Lok Sabha MPs aged 40 or under are effectively "hereditary", according to his research.

French said he was intrigued when the 2004 election returned a new generation of young MPs glowing with "a sense of bland entitlement" but whose main "achievement was usually to have shared genes with an earlier leader".

After the 2009 election, he gathered data on what factor was most influential in every MP's rise to power, with categories including family, student politics, business or trade union links.

He found that more than two-thirds of the 66 MPs aged 40 or under could be described as "hereditary" as their political families were the biggest factor in their success - though of course they still have to be voted in.

Among the ruling Congress Party, every single one of its 11 MPs aged under 35 had a "hereditary" path to power. And almost 70 percent of all female MPs were in politics through their family background.

Political succession is hardly new in India. Jawaharlal Nehru, the first prime minister after independence in 1947, began a dynasty in which his daughter, Indira Gandhi, and her son, Rajiv Gandhi, followed in his footsteps.

Rajiv's wife Sonia is the current president of the Congress party, and their son, Rahul, 40, is a high-profile member of parliament tipped for the top.

French argues that as India undergoes rapid economic development, the whole ruling elite is closing in on itself - and that rampant nepotism is storing up trouble for the future.

"There will be a backlash," French told AFP, saying that voters will eventually turn to fresh faces.

"At state level, there are a lot of ambitious, wealthy young politicians not from political families who want to push their way forward.

"The Lok Sabha situation was common knowledge in an anecdotal way but no one had looked at it statistically. It has got worse. I didn't expect the results to be so clear-cut."

French's book, "India: A Portrait", has created a stir among Delhi's chattering classes, with Outlook magazine's cover carrying the headline "Mummy-Papa MPs" over a cartoon of young lawmakers in prams.

Many reviews in Indian newspapers have praised the book for shining a light on how the country's politicians are keeping it in the family - though others point out that India's evolving democracy is less than 60 years old.

The raw data on MPs' backgrounds has been released at theindiasite.com, detailing the dense network of fathers, uncles and endless family connections behind each member.

Some MPs' biographies provide colourful variety, featuring former cricketers, film stars, low-caste "untouchables", deposed princes and tribal elders.

One, Kameshwar Baitha, is a Maoist commander who won his seat at the last election despite being in custody in a Bihar jail facing 46 criminal cases ranging from murder to extortion.

For French, the make-up of parliament is just one part of India's bewildering complexity as the country charges ahead with rapid industrial development and a sudden embrace of many Western values.

"I had a very depressing moment interviewing a man who spent years chained up in a quarry paying off his debts, and millions of Indians live a life not that different to his," he said.

"But I ended up more optimistic than I expected because whatever might be wrong with the politics or anything else, the general population in India is young and dynamic and the long-term trajectory is positive."