Qatar starts premarital genetic screening for all

DOHA // Six years after the law passing, Qatar has started mandatory premarital screenings this week, mainly to alert couples who may be related, of any potential health risks for their future offspring. About half of all marriages across Gulf nations are between cousins, and their frequency is increasing, according to a recent study in the Asian Pacific Journal of Cancer Prevention. At 54 per cent, the rate of cousin marriage appears highest in Qatar, and has increased nearly 30 per cent from the previous generation.

On its own, marriage between cousins, or consanguinity, is not necessarily problematic. But many debilitating genetic disorders - including sickle cell anaemia, cystic fibrosis, spinal muscular atrophy, mental retardation, epilepsy and Down syndrome - can be up to 20 times more frequent among populations in which cousin marriages are common. "It is certainly a problem," said Dr Ahmad Teeb. A genetics and paediatrics professor at the Weill Cornell Medical College of Qatar, he has been researching Arab genetic disorders for more than 25 years and contributed to the recent study.

"The issue here is not the cousin marriage, the issue here is to avoid the disease," Dr Teebi sai. "However, virtually none of us is free from carrying some bad genes, and when you are cousins the likelihood of you are carrying the same bad gene is higher." Marriage between second cousins or more distant relations has very little impact on the passing down of genetic disorders. Yet the children of first cousins, who share 12.5 per cent of their genes, are nearly twice as likely as the general population to contract a disorder. And within populations that intermarry regularly over generations, the coincidence of disorders can increase exponentially.

"If certain disorders are more common in a population," said Dr Teebi, "the likelihood of its occurrence can be many times increased." In the Gulf, most cousin marriages are between first cousins. A report by the Dubai-based Centre for Arab Genomic Studies (CAGS) in September found that a handful of genetic diseases - the blood disorder thalassaemia, diabetes and Down syndrome among them - have reached epidemic levels (more than 100 cases per 100,000) in several Gulf countries. The report also found that Arabs have one of the world's highest rates of genetic disorders, nearly two-thirds of which are linked to consanguinity.

Qatari leaders have been working to improve national health and medical awareness. This week, the Doha Exhibition Centre hosted Qatar Health 2009, an international forum for the latest advancements in health care research and technology. Sidra Medical and Research Center, a Qatar Foundation initiative that is backed by a US$7.9 billion (Dh29bn) grant and set to open in 2012, aims to become a regional centre of biomedical research and medical education.

Yet Qatar is the last Gulf nation to institute premarital screenings and many nationals remain unaware of the risks of marrying a close relation. A study to be published in Cambridge University's Journal of Biosocial Science next month found that most Qataris surveyed did not know that consanguinity had been linked to serious genetic diseases or that distant cousin marriages were genetically less risky than unions between first cousins.

"These results indicate that more effort needs to be made in developing public health strategies to improve the population's understanding of the cost-benefit analysis involved in contracting consanguineous marriages given the goal of healthy offspring," the report's authors wrote. Although cousin marriage is legal in 26 US states and across Europe, the rate of consanguinity in industrialised nations is generally less than one per cent. In Muslim countries, meanwhile, cousin marriage represents about 35 per cent 40 per cent of all unions. Research from CAGS and others suggests consanguinity is declining in Lebanon, Egypt and among Palestinians, but increasing in Morocco, Mauritania and Sudan.

It is also increasing across the Gulf. Dr Teebi links the trend to tribal tradition and the region's expanding economies. "Rich families tend to marry rich families, and from their own - and the rich like to protect their wealth," he said. "So it's partly economic, and it's also partly cultural." Qatar's Supreme Council of Health aims to change that culture, with an outreach campaign that includes workshops, online information, university lectures and the distribution of educational CDs and brochures. Earlier this week, the Qatari minister of public health, Abdullah bin Khalid al Qahtani said, "a healthy family is the basic cell of society".

The screenings are meant to strengthen that cell. Couples are tested for both communicable and genetic diseases. Doctors warn of any disorders likely to be passed to each other or to the couple's potential offspring, but cannot withhold a marriage licence due to any health risks. The final decision rests with the betrothed. "The couple will think twice or maybe three or four times," said Dr Teebi. He said that similar screenings in the UAE and Bahrain appear to have lowered the frequency of sickle cell anaemia.

"Some people might say, 'All right, we will take the risk,' and some will change their mind," he said. "It's the nature of humans that they will think about it." @Email:dlepeska@thenational.ae