Genetic combination of angiotensin-converting enzyme with methylene tetrahydrofolate reductase polymorphisms and the risk of type 2 diabetes mellitus in Bahrain.

INTRODUCTION: Bahrain has a high prevalence of type 2 diabetes mellitus (T2DM). Previously, Angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism was found to be associated with T2DM in Bahrainis. The relationship between the disease progression in Bahraini T2DM population and the genetic polymorphism of methylene-tetrahydrofolate-reductase (MTHFR) C677T is still under investigation. AIM: The current study investigated the distribution of MTHFR C677T gene polymorphism among Bahraini T2DM patients and examined the interaction between ACE I/D and MTHFR C677T polymorphisms on the risk of developing T2DM and its long-term complications. MATERIALS AND METHODS: Polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism (RFLP) were used to test for the presence of ACE I/D and MTHFR C677T polymorphisms in 171 patients with T2DM compared to 188 healthy (non-diabetic) age-matched control subjects from Bahrain. RESULTS: The incidence of the DD genotype and D allele of the ACE gene was high among Bahraini T2DM patients. MTHFR allele and genotype frequencies did not differ between patients and controls. No significant relationship was identified between the combinations of ACE I/D and MTHFR C677T polymorphisms with T2DM. CONCLUSIONS: The results clearly showed an association of the ACE I/D polymorphism with the progression of T2DM, but when it interacts with MTHFR polymorphism no influence was detected on the increased risk of T2DM.

Genotypes and allele frequencies of angiotensin-converting enzyme (ACE) insertion/deletion polymorphism among Bahraini population with type 2 diabetes mellitus and related diseases.

Insertion/deletion (I/D) polymorphism, of a 287-bp Alu repetitive sequence in intron 16 of the angiotensin-converting enzyme (ACE) gene has been shown to be associated with different types of diseases and has been widely investigated in different populations with different ethnic origins. Various reports were published suggesting inter-ethnic variations in the frequency of allelic forms of the ACE gene. The goal of this study was to test the distribution of alleles and the different genotypes of ACE (I/D) polymorphism in Bahraini subjects and compare the results with those obtained from other population studies. The Bahraini population is an Arabic peninsula population with a high prevalence of T2DM and hypertension. A total of 560 unrelated Bahraini individuals were recruited in this study and the presence (insertion)/absence (deletion) (I/D) polymorphism of a 287-bp Alu1 element inside intron 16 of the ACE gene was done by PCR-based assays and the presence or absence of the genotypes were analyzed by the gel electrophoresis. The distribution of II, ID, and DD genotypes showed differences among Bahraini subjects, and the frequency of the D allele was significantly (P < 0.05) higher in the studied group. The results obtained for the D allele are consistent with those obtained from previous studies among Arabs, Africans, and Caucasians, but differs significantly (P < 0.05) from those in Japanese and Chinese, thus proving the ethnic variation in the distribution of the ACE alleles in different populations.

Angiotensin-converting enzyme gene polymorphisms and T2DM in a case-control association study of the Bahraini population.

Bahrain has one of the highest incidence rates of type 2 diabetes mellitus (T2DM). Development of diabetic nephropathy (DN) as a complication was noticed in some patients while absent in others. This interesting observation raises the role of certain genetic risk factors for the development of DN. Angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism was found to be associated with T2DM. While some patients have predisposition to DN in the population, others have negative association. The present case-control association study was designed to investigate the association of ACE I/D polymorphism in T2DM patients in Bahrain especially in those who developed DN. A total of 360 T2DM patients (110 with DN and 250 without DN) and 360 healthy (non-diabetic) age-matched subjects were recruited for this study for comparison. The presence (insertion)/absence (deletion) (I/D) polymorphism of a 287-bp Alu1 element inside intron 16 of the ACE gene was investigated using PCR-gel electrophoresis. The results show that the distribution of the homozygote DD genotype of the ACE gene was high among Bahraini T2DM patients compared to the healthy non-diabetic subjects. In addition, the distribution of the deletion (D) allele was high among Bahraini T2DM patients with DN when compared to the healthy non-diabetic subjects. However, there was no significant difference in the distribution of ACE I/D allele and genotypes between DN patients when compared to those T2DM patients without DN. The results obtained in this study are in closely agreement with some previous reports which show a strong association of ACE polymorphism with T2DM patients, yet not a risk factor for development of DN.

P-type inositol phosphoglycans in serum and amniotic fluid in active pre-eclampsia.

OBJECTIVES: Abnormal secretion of P-type inositol phosphoglycans (IPG-P) has been described in maternal urine of pre-eclamptic women. The aim of this study was to determine the origin of production of IPG-P. We examined the IPG-P content of maternal and fetal serum, maternal urine and amniotic fluid in both normal pregnancy and pre-eclampsia. DESIGN: Established extraction and bioactivity assay techniques were used to compare total IPG-P levels in serum samples, and a polyclonal-antibody-based ELISA to assay the amniotic fluid and urine samples in matched pairs of women. SUBJECTS: Eleven women with pre-eclampsia requiring caesarean section (subjects), 11 pregnant women requiring elective caesarean section for reasons other than pre-eclampsia (controls). RESULTS: Our data confirm the abnormal level of IPG-P in maternal urine during pre-eclampsia. Moreover, IPG-P levels were higher in umbilical sera than in maternal sera samples. Amniotic fluid as well as urine ELISA results were significantly higher in the pre-eclamptic group compared with normal controls. Total IPG-P bioactivity in serum did not vary between serum compartments in normal pregnancy. Uterine vein IPG-P levels were lower in pre-eclampsia when compared with normal pregnancy. A possible correlation was observed between urine and amniotic fluid levels in normal women. No correlation was observed between measured blood levels and those in urine and amniotic fluid. CONCLUSIONS: It is hypothesized that steady state equilibrium of IPG-P in serum in normal pregnancy is disrupted in pre-eclampsia. Additionally, an abnormal IPG-P sub-fraction, detectable in urine and amniotic fluid, may be present and involved in the pathophysiology of the syndrome, although sites of production of this abnormal form remain unclear.