The UAE has a solid health-care infrastructure, good maternal care and low infant mortality rates, yet one of the highest incidence rates of genetic diseases globally. Why is it that in a country with relatively strong health care, genetic disorders are so common in our population?
The single most important factor is due to consanguineous marriages, or marriages between relatives. Unofficial estimates state that 30 to 50 per cent of all marriages among Emiratis are between close or distant relatives. Consanguinity may actually reach 70 per cent or higher in certain rural areas within the UAE. Add to this what is termed as the "founder effect" - meaning that a small population has an enriched gene pool (due to individuals coming from consanguineous marriages themselves) - and one can imagine the multiplier effect taking control very quickly.
From a genetic standpoint, the explanation is very simple: when one Emirati is a carrier of a certain genetic mutation, he or she is not directly affected by a genetic disease but simply carries a line of genetic code that is flawed. If that person marries a spouse with a similar genetic make-up (ie, carrier state), the result is a 25 per cent chance of an offspring who is fully affected by a genetic disease, a 50 per cent chance of being a carrier, and a 25 per cent chance of a healthy child who is not a carrier.
These health issues shed light on one topic that has been debated in The National in the past month: the social and cultural impact of marriages between Emiratis and foreigners. Sultan Sooud Al Qassemi's recent article explored how Emiratis from mixed marriages are an integral part of national development and no less Emirati in their patriotism and loyalty. However, one aspect of mixed marriages that has so far not been commented on is the potential medical benefits of cross-cultural unions from a genetic make-up point of view.
The genetics works the same whether an Emirati marries a foreigner or not - but the statistics are revealing. As of October 2006, the Centre for Arab Genomics database listed 228 genetic disease entries in the Arab population of the UAE. At present, this number exceeds 260, one of the highest figures for any nation globally. Only last year, 16 new genetic disorders were added to the list. According to local statistical data, 8 per cent of the Emirati population are carriers of the blood disease thalassaemia, more than 20 per cent have G6PD deficiency (an enzymatic defect), 25 per cent have some form of haemoglobin abnormality, and the prevalence of Down's syndrome is double the global average.
Only in neighbouring GCC countries, due to similar reasons of consanguineous marriage, can one find such extreme numbers. There are many very rare genetic disorders prevalent in Gulf countries; some are so rare worldwide that there are more people affected in the GCC than recorded on the entire continent of North America. In addition, it is not only genetic diseases that the Emirati population suffers from. The World Health Organisation states that nearly 20 per cent of Emirati breast cancer cases and 8 per cent leukaemia cases are due to strong genetic associations. Many other cancers show similar correlations.
On a brighter note, there have been several initiatives that seek to reduce these disease rates in the immediate future. Genetic screening programmes in some emirates offer premarital testing, and specialised laboratories are being developed to detect genetic disorders before they manifest. However, one needs to look at the future of medicine and genetics for a long-term solution. The "founder effect" can be regarded as both a curse and a solution. Due to the homogeneity of Emiratis and the small population, it has become extremely easy for scientists to determine what genetic mutations lead to what genetic disorders. For many of these diseases, there have not been diagnostic tests to verify their presence in the carrier state. Hence, the future is brighter than the statistics indicate, if as a nation we can utilise the data to our benefit through research.
Coming back to the issue of mixed marriages, previous articles have mentioned the social and economic benefits bestowed by mixed-parentage Emiratis; similarly, there are benefits of such marriages from a genetic standpoint too. However, mixed marriages are not the solution for most Emiratis. One cannot change cultural habits overnight, but we can educate ourselves about the risks of consanguineous marriages.
I have many Emirati friends who have married distant relatives, and made sure that both partners have been screened for the most common disease groups within our population, at the least, in order to avoid the uncertainty once they decide to have children. There are also generations of consanguineous marriages that have resulted in children who do not suffer from any type of genetic disorders. Perhaps the proper course is not to argue whether consanguineous marriages are right or wrong, especially when one is dealing with a complex tribal and cultural context. Instead, awareness of our genetic make-up should be an integral part of education and social participation, including the underlying statistics related to genetic disorders.
All Emiratis aspire to contribute to their country's profile, social welfare and economic development. We should also aspire to reduce the burden of healthcare costs on the nation by leading active and healthier lives, in order to curb the prevalence of diabetes, for example, for which the UAE is ranked second globally. In addition, I believe Emiratis will also aspire to reduce the prevalence of genetic diseases, similar to the higher profile diseases such as cancer and diabetes, through education and greater awareness.
Dr Ihsan Almarzouqi is an Emirati healthcare specialist with a background in genetics and an interest in health-care provision and policy
