Jordan Times
Monday, March 13, 2000
Rare hereditary disorder blamed on consanguinity
identified in four Jordanian villages
By Suha Ma'ayeh
AMMAN — A newly-discovered hereditary neurological disorder, which renders its victims partially paralysed, has been identified in four villages in the northern part of the Kingdom, where marriages among relatives remains a common practice.
A team of Jordanian and Cypriot doctors identified a rare hereditary disorder last year in the northern part of the Kingdom, which they blamed on consanguinity.
They called it Jerash Motor Neuronopathy after the northern region in the Kingdom where most patients come from.
Abdelkarim Qudah, a paediatric neurologist at the University of Jordan (UoJ), said the disorder attacks victims between 4-8 years of age causing weakness and muscle atrophy until patients become partially or completely disabled over the course of years.
“The disorder, which affects patients motor ability, is triggered by a genetic malformation barred by chromosome 9,” Qudah told the Jordan Times.
He pointed out that he and his colleagues from the UoJ and the Royal Medical Services were last year approached by two patients aged 4 and 12 who complained of utmost difficulty in walking.
“We studied their medical history and visited their village where we discovered similar cases,” Qudah added.
“But the symptoms manifested by such patients were different compared to other neurological disorders.
“This has prompted us to seek assistance from The Cyprus Institute of Neurology and Genetics.”
A study which surveyed a total of 84 individuals between the ages of 6-80 years clinically identified 27 affected patients. The patients came from nine highly consanguineous families all located within a cluster of villages in the Jerash Governorate. The male to female ratio was 1.7:1.
Initial symptoms revealed that all patients had difficulties in walking because of weakness in both feet.
According to the assessment conducted by Jordanian and Cypriot neurologists, 23 patients had weakness in the upper limbs.
“The disorder is not fatal...No drugs have been discovered so far,” Qudah said.
Doctors for years have stressed the need for conducting premarital testing to curb a wave of hereditary diseases that could result from intermarriages.
But sociologists and doctors argue that such tests remain rare in a conservative society because of social taboos, economic considerations and lack of health awareness, where marriages among relatives stands at nearly 51 per cent of all marriages.
“We need to raise awareness on premarital testing,” said Sami Khoury, a professor of community medicine at the University of Jordan.
“Intermarriages is a social and cultural phenomena...People need to be informed that the product of such marriages increases the chances of genetic disorders,” Khoury told the Jordan Times.
Another disorder identified last year by Jordanian doctors was dubbed Kufor-Rakeb after the village where it originated.
The disease hits patients in their teens and renders them bed bound and totally dependent on their families.
All affected patients have expressionless faces, with weak facial muscles leaving them with a staring look. Besides, constant drooling becomes a major problem as the disease progresses.
The Ministry of Health spends millions of dinars annually to treat patients diagnosed with hereditary diseases. So far, most government campaigns calling for premarital tests to cut possible abnormalities have been shy.
On average, the health ministry spends JD4 million annually on some 800 patients with thalassaemia — a genetically transmitted disease.
Patients hit with Kufor-Rakeb also cost the ministry JD20,000 each.
Treatment of such disorders and other chronic diseases place huge financial constraints on the ministry's limited budget.
The ministry launched the idea of mandatory testing for to-be couples only six years ago. But it has left it up to them to decide whether or not to tie the knot if tests indicate that problems may arise if the couple decides to have children.
Last year the health ministry said it had assigned 29 centres across the Kingdom to offer premarital testing, but neurologists say that Jordan lacks specialised centres to carry out DNA testing. Neurologists instead send their samples abroad for specialised testing.
In a conservative country where traditions are cherished, consanguinity continues a widespread practice among Jordanians.
Doctors agree that social traditions, religion, education and family pressures are decisive factors in a society where arranged marriages constitute 80 per cent of the total marriages.
“The problem (intermarriages) is more of a social one than being medical. A mother fears if she conducts premarital tests that prove she is a carrier of a defected gene, she will end up being divorced,” said Qudah.
Others blame their woes on fate.
“All my 10 children are disabled,” said a white-haired man at a public hospital.
“It is God's will,” said the man who believed it was worth trying to father so many children, lest one of them will free of disability.
Neurologists acknowledge that such a scenario remains common, especially in impoverished areas where illiteracy prevails.
Khoury, along with Diana Massad, who is an assistant researcher, conducted a two-part community-based study on consanguinity this year and in 1992.
In their studies, they both concluded that the products of such marriages are at higher risks of congenital malformations, still births, and a higher infants mortality rate compared to non-consanguineous marriages.
Congenital malformations and familial diseases ranged from cardiac defects, congenital dislocation of the hip, blindness, asthma to diabetes.
This year's study, which surveyed 1,867 couples revealed that 51 per cent of marriages were consanguineous.
The study, which explored health effects of consanguinity on fertility, infant mortality and still births, congenital malformations, revealed that the most prevailing type of consanguineous marriage was found to be first cousins type 1 (paternal cousins) with 20 per cent of the total sample.
The study showed that fertility as measured by the number of pregnancies, taking into consideration marriage duration was not affected by consanguinity.
Twin pregnancies and abortions did not show any significant difference between consanguineous and non-consanguineous marriages.
But, consanguineous marriages showed significantly higher rates of still births, infant mortality and congenital malformations.
In the total sample, 77 instances of congenital malformations were reported by mothers at a rate of 13.7/1000 live births.
Malformations reported in the consanguineous group amounted to 50 (17.5/1000 consanguineous live births) as compared to 27 (9.8/1000 non consanguineous live births).
Within the same consanguineous group, female infant mortality rates were significantly higher than those of males.