Pan Arab Genetics
Expert calls for preventive programmes in Arab world
2nd Pan Arab Human Genetics Conference discusses ethics, issues Dubai Declaration

There is an urgent need to establish, improve and expand preventive programmes across the Arab world to alleviate the costly burden of treating and managing disease that results from genetic disorders (GD), says Ghazi Omar Tadmouri, assistant director, Centre for Arab Genomic Studies (CAGS), Dubai.

Tadmouri raised the issue at the 2nd Pan Arab Human Genetics Conference in Dubai from 20-22 November, which was attended by leading geneticists, physicians and administrators from around the world.

“Genetic disorders in most cases result in chronic and lifelong diseases. In the Arab world some of these are epidemic such as sickle cell anaemia, beta thalassaemia and diabetes mellitus,”

Tadmouri said during his presentation on Genetic Disorders in Arab Populations. He also highlighted the work that goes into the CTGA (Catalogue of Transmission Genetics in Arabs) database.

He said there was little information regarding the economics of GD in the Arab world, “although it is known that people afflicted with GD require more frequent hospital visits and, in many cases, undergo a higher number of surgeries than other patients”.

“The total costs they pay are generally higher than other patients,” he pointed out, adding that in many cases GD patients are from more remote areas, where families are extended and there is a higher prevalence of consanguinity (intermarriage). These patients have to travel far to receive treatment.”

To illustrate the point, Tadmouri referred to the annual average cost per patient of treatment for certain genetic disorders in the United States and extrapolated these figures to give a rough estimate of the annual cost of treatment in the Arab world. For example, the annual cost of treating a single beta thalassaemia patient in the US is US$7,000.

“If there are 100,000 thalassaemia patients in the Arab world then we are looking at about $700 million to treat these patients every year. And this is just the cost of hospitalisation. It does not include indirect or any tangible costs outside the hospital,” he emphasised.

“These are rough estimates and they will fluctuate depending on the severity of the disease, nonetheless, it is a very costly burden.” In the US, treatment for permanent child hearing impairment costs around $26,000 a year per patient, cystic fibrosis costs around $9,400, sickle cell anaemia $6,300, diabetes mellitus $1,200 and haemophilia $1,000.

“To alleviate this burden, preventive programmes must be established. These include newborn and GD carrier screening programmes,” he said. Tadmouri also called for extensive education initiatives.

Dr Danuta Krotoski, of the US National Institutes of Health, spoke specifically about newborn screening, which is now mandatory across the US. “Most states screen for at least 29 genetic disorders, some for even more,” she pointed out.

“Establishing a national newborn screening programme is no light matter. Therefore it is essential that a thorough knowledge of the epidemiology of GD in the region is known, before deciding what diseases to screen for,” she said.

Dr Krotoski noted that in November 2006 the Marrakech Declaration was issued following a conference in that Moroccan city dealing specifically with newborn screening.

Among a number of recommendations, the declaration calls on all countries in the Middle East North Africa (MENA) region “to establish a systematic national newborn screening programme” as part of a global policy for children’s health.

A copy of the Marrakech Declaration can be found online at: www.ipa-world.org/news/news/marrakechDeclaration.pdf

CTGA database

Citing data collected for the CTGA database, Tadmouri said there are more than 200 genetic disorders among the Arab population in the UAE.

“Congenital abnormalities and chromosomal malformations are most common in the Arab world,” he said. “Autosomal recessive disorders (cystic fibrosis, sickle cell anaemia) are more common than autosomal dominant disorders, except in Bahrain,”

Tadmouri noted, adding that Bahrain had significantly decreased the incidence of consanguinity in the past 20 years, which could be the reason for this finding. The CTGA database was established and began collecting GD information in 2004, initially only from the UAE.

From September 2006 it was extended to include Bahrain and, more recently Oman. “We have now nearly completed collecting GD information from Oman and will in future expand it to include other countries in the region,” Tadmouri told the conference.

“The CTGA database is similar to OMIM,” explained Tadmouri. OMIM – Online Mendelian Inheritance in Man – is a database cataloguing human genes and genetic disorders authored and edited by Dr Victor A.

McKusick and his colleagues at Johns Hopkins and elsewhere, and developed for the World Wide Web (www.ncbi.nlm.nih.gov/sites/entrez?db=OMIM). Like OMIM, the CTGA database is accessible to the public on the Internet, but is intended for physicians, geneticists and researchers. It can be accessed online at: www.cags.org.ae. The database provides detailed descriptions of GDs and their epidemiology in the Arab world.

Geneticists and physicians in the region are asked to contribute their GD findings to the database via a form available at the database website. “Many GDs are specific to the Arab world,” said Tadmouri. “And around 33% of GDs in Arabs have yet to be mapped.”

Unified system

Tadmouri called for a unified system of clinical and molecular reporting, particularly in international journals, where GDs in Arab individuals are researched without including the specific geographical location of the Arab individual.

He said CAGS researchers have discovered through the CTGA that GDs in the Arab world are location-specific and it was important when publishing research that the specific geographical location of the Arab individual in question be noted.

“Out of all the genetic disorders in the UAE, Bahrain and Oman only about 22% are common to the three countries,” he said.

Another issue, Tadmouri said, is that between 70-90% of papers dealing with GDs in the Arab world are merely clinical reports. “The molecular pathologies remain unknown.”

Human Variome Project

Also at the 2nd Pan Arab Human Genetics Conference, Professor Richard Cotton, the director of the Human Variome Project (HVP) (www.humanvariomeproject.org) explained the reasons behind the initiative and some of the challenges the HVP faced.

The HVP is a global initiative which aims to catalogue all human gene variations to provide an open resource of human variance and its phenotype for researchers, clinicians and patients.

To emphasise the need for the HVP, Prof Cotton pointed out that more than 60% of all humans will be affected by genetic mutation in their lifetime. “In one US paediatric hospital, for example, 70% of admissions had genetic disorders,” he noted.

“Putting the HVP together is a complicated activity,” he said. “It involves the establishment of a multinational committee with a wide range of responsibilities and tasks.”

Draft working groups have been established. He said the HVP faced a number of challenges, such as a lack of funding, the need to collate data from a large number of mutation databases around the world each with differing levels of curation; there is no formal method of data collection; and in some cases there is commercial protection of data.

He said it was important that the profile of the HVP was raised which would involve the participation of organisations such as the WHO, UNESCO, OECD, EC, CDC and publications such as Nature Genetics. He said what was needed was an increased ‘flow of mutation data’ from countries around the world to mutation databases and requested those in a position to provide this information to visit the Human Genome Variation Society website: www.hgvs.org, which provides guidelines for submitting this data and detailed information about the HVP. 

 Date of upload: 22nd Jan 2008