There's nothing wrong with cousins getting married, scientists say

Risk of babies having genetic defects 'has been overstated'

The risk of giving birth to babies with genetic defects as a result of marriages between first cousins is no greater than that run by women over 40 who become pregnant, according to two scientists who call for the taboo on first-cousin families to be lifted.

Women in their forties are not made to feel guilty about having babies and the same should apply to cousins who want to marry, said Professor Diane Paul of the University of Massachusetts in Boston and Professor Hamish Spencer of the University of Otago in Dunedin, New Zealand. Although first-cousin marriages are legal in Britain, there have been calls to ban the practice because of reports that it has resulted in a higher-than-average incidence of birth defects in certain immigrant communities where it is common and culturally acceptable.

However, Professors Paul and Spencer said that the risk of congenital defects is about 2 per cent higher than average for babies born to first-cousin marriages – with the infant mortality about 4.4 per cent higher – which is on a par with the risk to babies born to women over 40. "Women over the age of 40 have a similar risk of having children with birth defects and no one is suggesting they should be prevented from reproducing," said Professor Spencer, whose co-authored study is published in the online journal Public Library of Science.

First-cousin marriages were once quite common in Europe, especially among the elite – Charles Darwin married his first cousin Emma Wedgwood – but that changed in the late 19th-century as people, especially women, became more socially mobile and the risks became more evident. The stigma attached to first-cousin marriages was supported by early studies into human genetics suggesting that "recessive" versions of a gene (which are not expressed unless there are two of them, one from each parent) are more likely to be expressed in the children of genetically related parents, as well as more likely to be defective.

Most states in America have either outlawed or restricted the practice, as has China, Taiwan and both North and South Korea. Professor Spencer, an evolutionary zoologist, said these laws should be repealed, especially in America, where he said they were drafted in a way that discriminated against the rural poor and immigrants: "Neither the scientific nor social assumptions behind such legislation stand up to close scrutiny. Such legislation reflects outmoded prejudices about immigrants and the rural poor and relies on over-simplified views of heredity. There is no scientific grounding for it."

In the UK, the issue came to the fore when the MP Phil Woolas, now the Immigration minister, claimed earlier this year that first-cousin marriages within Asian communities in Britain resulted in an increasing number of children with health problems. "A lot of arranged marriages are with first cousins, and that produces lots of genetic problems in terms of disability [in children]," Mr Woolas said.

Peter Corry of St Luke's Hospital in Bradford estimates that among people of Pakistani descent in the city, 55 per cent of whom marry first cousins, the risk of recessive genetic disorders – the type due to related parents – is between 10 and 15 times higher than in the general population. A 2004 study found that 13 out of 1,000 Asian children born in the Bradford area had inherited recessive disorders, which can lead to disabilities.

A family affair: Cousins who tied the knot

Jerry Lee Lewis

The rock 'n 'roll star infamously married his 13-year-old first cousin once removed, 10 years his junior, in 1957. His popularity initially fell but recovered when he began performing country and western music.

Jesse James

The Missouri outlaw married his first cousin Zerelda "Zee" Mimms in 1874 at the height of the James-Younger gang's reign. They had two children and remained together until Jesse's death, aged 34, 12 years later.

H G Wells

The science fiction author of The Time Machine and The War of the Worlds married his first cousin Isabel Mary Wells in 1891 but left her after three years to marry one of his students, with whom he had two children.

Edgar Allan Poe

The American gothic poet secretly married his 13-year-old first cousin, Virginia Eliza Clemm, in 1834. She died of tuberculosis in 1847.

Johann Sebastian Bach

In 1707 Bach married his second cousin Maria Barbara Bach and had seven of his 20 children with her.

Khalid Mahmood

The Birmingham MP married his first cousin, Rifat, when he was in his twenties. They had a child – now a teenager – but separated in 1992.

Charles Darwin

The naturalist, whose work forms the basis for contemporary evolutionary theory, married his first cousin Emma Wedgwood in 1839. They had 10 children, to whom he was a devoted father.

Start your day with The Independent, sign up for daily news emails
PROMOTED VIDEO
News
Tangerine Dream Edgar Froese
people
News
Rob Lowe
peopleRob Lowe hits out at Obama's snub of Benjamin Netanyahu
News
Davies (let) says: 'Everybody thought we were having an affair. It was never true!'
people'Our friendship flourished online. You can share some very revelatory moments at four in the morning…'
Arts and Entertainment
Over their 20 years, the band has built a community of dedicated followers the world over
music
News
Staff assemble outside the old City Road offices in London
mediaThe stories, the writers and the changes over the last quarter of a century at Britain's youngest paper
Life and Style
The Oliver twins, Philip and Andrew, at work creating the 'Dizzy' arcade-adventure games in 1988
techDocumentary looks back at origins of the computer-games industry
ebooks
ebooksA year of political gossip, levity and intrigue from the sharpest pen in Westminster
Arts and Entertainment
Krall says: 'My hero player-singer is Elton John I used to listen to him as a child, every single record
music
News
Friends for life … some professionals think loneliness is more worrying than obesity
scienceSocial contact is good for our sense of wellbeing - but it's a myth that loneliness kills, say researchers
Arts and Entertainment
The Wu-Tang Clan will sell only one copy of their album Once Upon A Time In Shaolin
musicWu-Tang Clan and The Sexual Objects offer fans a chance to own only copies of their latest albums
News
i100
Environment
Number so freshwater mussels in Cumbria have plummeted from up to three million in the 20th century to 500,000
environment
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Austen Lloyd: Private Client Solicitor - Oxford

Excellent Salary : Austen Lloyd: OXFORD - REGIONAL FIRM - An excellent opportu...

Austen Lloyd: Clinical Negligence Associate / Partner - Bristol

Super Package: Austen Lloyd: BRISTOL - SENIOR CLINICAL NEGLIGENCE - An outstan...

Recruitment Genius: Sales Consultant - Solar Energy - OTE £50,000

£15000 - £50000 per annum: Recruitment Genius: Fantastic opportunities are ava...

Recruitment Genius: Compute Engineer

Negotiable: Recruitment Genius: A Compute Engineer is required to join a globa...

Day In a Page

Iraq invasion 2003: The bloody warnings six wise men gave to Tony Blair as he prepared to launch poorly planned campaign

What the six wise men told Tony Blair

Months before the invasion of Iraq in 2003, experts sought to warn the PM about his plans. Here, four of them recall that day
25 years of The Independent on Sunday: The stories, the writers and the changes over the last quarter of a century

25 years of The Independent on Sunday

The stories, the writers and the changes over the last quarter of a century
Homeless Veterans appeal: 'Really caring is a dangerous emotion in this kind of work'

Homeless Veterans appeal

As head of The Soldiers' Charity, Martin Rutledge has to temper compassion with realism. He tells Chris Green how his Army career prepared him
Wu-Tang Clan and The Sexual Objects offer fans a chance to own the only copies of their latest albums

Smash hit go under the hammer

It's nice to pick up a new record once in a while, but the purchasers of two latest releases can go a step further - by buying the only copy
Geeks who rocked the world: Documentary looks back at origins of the computer-games industry

The geeks who rocked the world

A new documentary looks back at origins of the computer-games industry
Belle & Sebastian interview: Stuart Murdoch reveals how the band is taking a new direction

Belle & Sebastian is taking a new direction

Twenty years ago, Belle & Sebastian was a fey indie band from Glasgow. It still is – except today, as prime mover Stuart Murdoch admits, it has a global cult following, from Hollywood to South Korea
America: Land of the free, home of the political dynasty

America: Land of the free, home of the political dynasty

These days in the US things are pretty much stuck where they are, both in politics and society at large, says Rupert Cornwell
A graphic history of US civil rights – in comic book form

A graphic history of US civil rights – in comic book form

A veteran of the Fifties campaigns is inspiring a new generation of activists
Winston Churchill: the enigma of a British hero

Winston Churchill: the enigma of a British hero

A C Benson called him 'a horrid little fellow', George Orwell would have shot him, but what a giant he seems now, says DJ Taylor
Growing mussels: Precious freshwater shellfish are thriving in a unique green project

Growing mussels

Precious freshwater shellfish are thriving in a unique green project
Diana Krall: The jazz singer on being friends with Elton John, outer space and skiing in Dubai

Diana Krall interview

The jazz singer on being friends with Elton John, outer space and skiing in Dubai
Pinstriped for action: A glimpse of what the very rich man will be wearing this winter

Pinstriped for action

A glimpse of what the very rich man will be wearing this winter
Russell T Davies & Ben Cook: 'Our friendship flourished online. You can share some very revelatory moments at four in the morning…'

Russell T Davies & Ben Cook: How we met

'Our friendship flourished online. You can share some very revelatory moments at four in the morning…'
Bill Granger recipes: Our chef serves up his favourite Japanese dishes

Bill Granger's Japanese recipes

Stock up on mirin, soy and miso and you have the makings of everyday Japanese cuisine
Michael Calvin: How we need more Eric Cantonas to knock some sense into us

Michael Calvin's Last Word

How we need more Eric Cantonas to knock some sense into us