This study was conducted on 3212 Saudi families to investigate the prevalence of consanguineous marriages. The families were interviewed and the information on the relationship between the husband and wife was obtained. The overall rate ofconsanguinity shows that 57-7% ofthe families screened were consanguineous. The most frequent were first cousin marriages (28-4%) followed by distant relative marriages (15-2%) and second cousin marriages (14-6%).The families were grouped according to the province of their origin and the consanguinity rates were calculated accordingly. There were slight differences in the consanguinity rates in the five provinces, which ranged from 52-1% to 67-7%. In each province first cousin marriages were the most frequently encountered pattern, ranging from 17-90/o to 40-90/o. The inbreeding coefficient (F) was calculated for each province and ranged from 0-020 to 0O030.Within each province, there were several significant differences among the populations in the different areas. The highest rate ofconsangiinity was 80O6% in Samtah and the lowest rate was around 34% in Abha in the South Western province.These results place Saudi Arabia among the countries of the world with a high rate of consanguinity. The possible consequences of increased consanguinity are presented and discussed.

No abstract

This study was undertaken to determine the prevalence of diabetes mellitus (DM), insulin-dependent diabetes mellitus (IDDM), noninsulin-dependent diabetes mellitus (NIDDM) and impaired glucose tolerance (IGT) in different areas of Saudi Arabia. A household survey was conducted in 34 different areas of Saudi Arabia. Demographic data and medical history were taken and filled. Fasting and two-hour "post-glucose load" blood samples were collected from 23,493 Saudi males and females and blood glucose was estimated immediately. The diagnoses of DM and IGT were made based on the criteria of the World Health Organization (WHO). Diabetic patients were subgrouped as IDDM and NIDDM on the basis of age of onset and mode of treatment. In the overall group (two to 70 years), the prevalence of IDDM, NIDDM and IGT was 0.193%, 5.503% and 0.498% in the Saudi males and 0.237%, 4.556% and 0.900% in the Saudi females. When grouped on the basis of age, there were 8762 children (<14 years). Of these children, 15 (0.171%) had IDDM and 13 (0.148%) had maturity onset diabetes of the young (MODY). The prevalence of IGT in this group was 0.250%. In the 14-70-year age group, the prevalence of IDDM, NIDDM and IGT was 0.239%, 9.50% and 0.717% in the males and 0.248%, 6.820% and 1.347% in the females, respectively. A significant increase (P<0.001) was obvious in the age group >30 years, where the prevalence of NIDDM and IGT rose to 17.32% and 1.30% in the males and 12.18% and 2.2% in the females, respectively. IDDM showed a slight decrease in those over the age of 60 years. These results place Saudi Arabia among the countries that have a high prevalence for DM and a moderate risk for IGT. In light of these findings, it is clear that carefully planned programs are needed to achieve control and prevention of diabetes mellitus in Saudi

Insulin-dependent diabetes mellitus (IDDM) is a frequent complication in patients with beta-thalassaemia major. It is believed to be a consequence of the damage inflicted by iron overload to the pancreatic beta-cell. Liver disorders and genetic influences seem to be additional predisposing factors to diabetes mellitus in patients with beta-thalassaemia. Ethnic variations are frequently reported on prevalence and complications of diabetes mellitus in the beta-thalassaemia patients. We investigated 50 Saudi children (< 15 years) with beta-thalassaemia major and 50 beta-thalassaemia minor, and age- and sex-matched controls for the prevalence of diabetes mellitus, and its relation to hitherto claimed predisposing factors. Fasting blood glucose, plasma insulin level, liver function tests, plasma ferritin, iron, and transferrin were assessed in each patient and glucose tolerance was evaluated. Results in patients with beta-thalassaemia major were compared with those obtained for beta-thalassaemia minor and the controls. The results showed moderate elevation of ferritin level in the majority of the beta-thalassaemia major despite desferroxamine therapy. Either hyperinsulinaemia or hypoinsulinaemia was encountered in the majority of these patients. The prevalence of diabetes mellitus was 6 per cent compared to 2 per cent in the beta-thalassaemia minor and normal children. Impaired glucose tolerance (IGT) occurred at a significantly higher (24 per cent) frequency in the beta-thalassaemia major compared to 2 and 0 per cent in the beta-thalassaemia minor patients and normal controls, respectively. The prevalence of diabetes mellitus was significantly lower in the Saudi thalassaemic patients compared to the results obtained from patients of other ethnic groups reported in literature.(ABSTRACT TRUNCATED AT 250 WORDS)

The frequencies of glucose-6-phosphate dehydrogenase (G-6-PD), pyruvate kinase (PK) and hexokinase (HK) deficiency were determined in different regions of Saudi Arabia. G-6-PD deficiency was found to range from 0.045 to 0.220 for the male and 0.020 to 0.125 for the female population. The highest frequencies were found to exist in the regions which are endemic to malarial parasite and have high frequencies of sickle cell and thalassaemia genes. Partial deficiencies of PK and HK were encountered in each region, however, no case of complete deficiency of these enzymes was identified. Further investigations are in progress to determine the clinical manifestations of enzyme deficiencies in the Saudi population.