Impact of right ventricular diastolic dysfunction on clinical outcomes in inferior STEMI.

BACKGROUND: The aim of this study was to investigate the prognostic value of restrictive right ventricular filling pattern (RRVFP) in patients with the first acute inferior wall myocardial infarction (IWMI) complicated by right ventricular myocardial infarction (RVMI) undergoing primary percutaneous coronary intervention (p-PCI). METHOD: A total of 152 patients with acute IWMI complicated by RVMI undergoing p­PCI were divided into two groups according to the presence of RRVFP. RRVFP was defined as tricuspid diastolic early/late flow velocities (Et/At) > 2 and Et deceleration time (DT) < 120 ms. RESULTS: There were 23 patients with RRVFP in the study cohort. At, DTt, isovolumetric relaxation time (IVRT), and tissue Doppler tricuspid annular late velocity (A't) were reduced significantly in patients with RRVFP than in those without RRVFP (At 19.6 ± 2.7 vs. 39.1 ± 7.4 cm/s, p < 0.001; DTt 106 ± 13 vs.156 ± 21 ms, p = 0.001; IVRT 59 ± 6.7 vs. 62 ± 7.4 ms, p = 0.01; A't 4.6 ± 1.1 vs. 8.6 ± 1.05, p = 0.001). Et/At ratios were higher in patients with RRVFP than in those without RRVFP (Et/At 2.20 ± 0.2 vs. 1.15 ± 0.37, p < 0.001). Et, tissue Doppler tricuspid annular early velocity (E't), E't/A't ratio, and Et/E't ratio were not significantly different between groups (Et 43.3 ± 5.4 vs. 40.7 ± 9.2 cm/s p = 0.18; E't 8.8 ± 1.4 vs. 9.5 ± 2.3, p = 0.15; E't/A't 1.08 ± 0.24 vs. 1.13 ± 0.30, p = 0.52; Et/E't ratio 5.0 ± 1.1 vs. 4.5 ± 1.5 p = 0.09). Presence of E't/A't > 2, short DTt, RRVFP, unsuccessful p­PCI, and cardiogenic shock on admission were independent predictors of in-hospital mortality (p < 0.05) in multivariable logistic regression analysis. CONCLUSION: Presence of RRVFP is associated with in-hospital mortality in patients presenting with their first IWMI complicated by RVMI.

Auditory changes in acromegaly.

OBJECTIVE: The aim of this study is to determine the changes involving auditory system in cases with acromegaly. MATERIALS AND METHODS: Otological examinations of 41 cases with acromegaly (uncontrolled n = 22, controlled n = 19) were compared with those of age and gender-matched 24 healthy subjects. Whereas the cases with acromegaly underwent examination with pure tone audiometry (PTA), speech audiometry for speech discrimination (SD), tympanometry, stapedius reflex evaluation and otoacoustic emission tests, the control group did only have otological examination and PTA. Additionally, previously performed paranasal sinus-computed tomography of all cases with acromegaly and control subjects were obtained to measure the length of internal acoustic canal (IAC). RESULTS: PTA values were higher (p < 0.001 for right ears and p = 0.001 for left ears), and SD scores were (p = 0.002 for right ears and p = 0.002 for left ears) lower in acromegalic patients. IAC width in acromegaly group was narrower compared to that in control group (p = 0.03 for right ears and p = 0.02 for left ears). When only cases with acromegaly were taken into consideration, PTA values in left ears had positive correlation with growth hormone and insulin-like growth factor-1 levels (r = 0.4, p = 0.02 and r = 0.3, p = 0.03). Of all cases with acromegaly 13 (32%) had hearing loss in at least one ear, 7 (54%) had sensorineural type and 6 (46%) had conductive type hearing loss. CONCLUSION: Acromegaly may cause certain changes in the auditory system in cases with acromegaly. The changes in the auditory system may be multifactorial causing both conductive and sensorioneural defects.

Radio-protective effects of Nigella sativa oil on oxidative stress in tongue tissue of rats.

OBJECTIVE: The aim of this study was to evaluate the effects of Nigella sativa (N.S.) oil against radiation-induced oxidative stress in the rat tongue. MATERIAL AND METHODS: Thirty-two Sprague-Dawley rats were randomly divided into four equal groups. Group 1 [control group(C)] did not receive N.S. oil or irradiation. Group 2 [sham control group(CN)] did not receive N.S. oil or irradiation but received 1-ml saline orally, plus sham irradiation. Group 3 [irradiation group(R)] received irradiation, plus 1-ml saline orally. Group 4 [irradiation plus N.S. oil group(RN)] received irradiation plus 1 g kg(-1) per day of N.S. oil orally for 10 days. The animals were euthanized on day 10, and tongue tissues were collected for evaluating biochemical oxidative parameters. RESULTS: The oxidative stress index, total oxidant status and lipid hydroperoxides levels in the R group were statistically higher than those in the C, CN and RN groups. The paraoxonase levels in the R group were statistically lower than those in the C, CN and RN groups. No statistically significant differences were detected between any of the groups, in terms of total antioxidant status and the arylesterase, ceruloplasmin and total sulfhydryl group levels. CONCLUSION: Nigella sativa (N.S.) oil may be a beneficial agent in protecting against ionizing radiation-related tissue injury.

The value of NT-pro-brain natriuretic peptide and left ventricular ejection fraction for prediction of premature ventricular complexes burden.

OBJECTIVE: We aimed to investigate the relation of NT-pro BNP level and left ventricular ejection fraction with premature ventricular complex burden. PATIENTS AND METHODS: A total of 94 patients with PVC burden > 5% (age 45.9+12.9 years, 53 males, 41 females) were included in the study. The primary outcome was PVC burden % and main prognostic factors were LVEF% and NT-Pro BNP level. Gender, age, DM, HTN, presence of symptoms, symptom duration and heart rate were used as adjustment predictor variables. We created four different linear multivariable models to compare performance measures of prognostic factors: Model-1 has gender, age, DM, HTN, symptoms and heart rate, while LVEF has been added in addition to model-1 in model-2. Model-3 included NT-Pro-BNP alongside model-1 variables, while model-4 included both LVEF and NT-Pro-BNP variables in addition to model-1 variables. Accordingly, we compare the performance (R2, likelihood ratio X2) of models. RESULTS: The median PVC burden was 18% (IQR; 11-27). When model-1 consisting of gender, age, DM, HTN, presence of symptoms, symptomS duration and heart rate and model-2 consisting of LVEF in addition to variables of model-1 were compared, it was observed that both LRX2 and R2 values improved (likelihood ratio test p-value=0.013). Model-1 compared with model-3 which consisting of NT-pro BNP in addition to variables of model-1, and it was observed that both LRX2 and R2 values improved (likelihood ratio test p-value=0.008). However, when compared to model-1, the most significant improvement was observed in both LRX2 and R2 values in model-4 consisting of model-1 plus NT-Pro-BNP and LVEF (likelihood ratio test p-value <0.001). CONCLUSIONS: We determined that NT-pro-BNP levels and LVEF could predict PVC burden in patients. Higher levels of NT-pro-BNP and lower LVEF values were associated with increased PVC burden.

Evaluation of the effect of bun/albumin ratio on in-hospital mortality in hypertensive COVID-19 patients.

OBJECTIVE: The impact of COVID-19 infection still continues all over the world and is an important cause of mortality. The mortality rate due to infection varies between 1-5%. The mortality rate is higher in those with cardiovascular risk factors, especially in cases with hypertension. Some studies have shown that blood urea nitrogen (BUN) and albumin levels are associated with worse prognosis in patients with COVID-19. In our study, we aimed to investigate whether the BUN/albumin (BAR) ratio has an effect on in-hospital mortality in hypertensive COVID-19 patients. PATIENTS AND METHODS: A total of 800 hypertensive COVID-19 patients, (618 of whom were alive and 182 died) were included in our study. Patients with a history of heart failure, malignancy, acute coronary syndrome, and myocarditis were excluded. RESULTS: The median age of the study population was 69 (60-77 IQR) years, and 305 (38%) of these patients were men. There was no statistically significant difference between the patients who died during follow-up and cases that remained alive in terms of comorbidities except chronic obstructive pulmonary disease (COPD) which was significantly lower in surviving group (p=0.014). Multivariable logistic regression analysis revealed that age [OR: 1.04, CI (1.01-1.06); p=0.002], male gender [OR: 1.85, CI (1.13-3.02); p=0.010], lymphocyte count [OR: 0.63, CI (0.40-0.98); p=0.038], SaO2 [OR: 0.82, CI (0.79-0.85); p<0.001] and BAR level [OR: 1.09, CI (1.04-1.16); p=0.001] were independent predictors of in-hospital mortality. ROC analysis yielded that BAR is a better predictor of in-hospital mortality compared to albumin and BUN alone. CONCLUSIONS: BUN, albumin, and BAR levels were found to be reliable predictors of in-hospital mortality in COVID-19 patients, and BAR was also found to be a more reliable predictor than BUN and albumin levels. Hypertension is one of the major risk factors for morbidity and mortality in COVID-19 and, BAR presents additional prognostic data in hypertensive COVID-19 patients that may direct physicians for treatment intensification.

The role of high frequency tympanometry in newborn hearing screening programme.

BACKGROUNDS AND OBJECTIVE: The hearing assessment of the newborns ideally should detect both middle and inner ear functions. The aim of this study is to control the association between otoscopic evaluation, multifrequency tympanometry and TEOAE results. METHODS: Fifty new-borns otherwise healthy were tested after the otolaryngological evaluation by 226 and 1000 Hz tympanometries and transient evoked otoacoustic emissions (TEOAE's). The study was performed in three steps and 17 babies that could not pass from the first step they were tested in the second step with the same tests (226 Hz and 1000 Hz tympanometry and TEOAE) The babies that could not pass from the second step were evaluated by multifrequency tympanometries, TEOAE and acoustic brainstem responses (ABR) at the third step. RESULTS: The association between the results obtained from otoscopic evaluation, multifrequency tympanometry and TEOAE were assessed. We found that 1000 Hz tympanometry results were more sensitive and gives more correlated with TEOAE and otoscopic evaluation. CONCLUSIONS: Multifrequency tympanometry can detect the middle ear pathologies of the infants sensitively and should be a part of neonatal hearing screening test battery.

Serum paraoxonase, arylesterase activity and oxidative status in patients with obstructive sleep apnea syndrome (OSAS).

INTRODUCTION: The aim of this study was to evaluate the serum paraoxonase (PON), arylesterase activities, lipid hydroperoxide (LOOH), sulfhydryl (-SH), and ceruloplasmin (Cp) levels, total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI) in adults with obstructive sleep apnea syndrome (OSAS) and to determine whether these oxidant and antioxidant levels can be used as OSAS markers. The results were compared with measurements from healthy control subjects. METHODS AND METHODS: This study was a prospective, controlled trial including 26 OSAS patients and 35 healthy controls (61 subjects total). Peripheral venous blood samples were taken from the OSAS patients and from the healthy volunteers. The serum PON, arylesterase activities LOOH, -SH, Cp, TAS, TOS, and OSI levels were measured. RESULTS: LOOH and Cp levels were higher in the OSAS group than in the control group (p < 0.01). The -SH levels were lower in the OSAS group than in the control group (p < 0.01). The PON and arylesterase enzyme activity levels were lower in the OSAS group than in the control group (p < 0.05). The TOS and OSI levels were significantly higher in the OSAS group (p < 0.01), while their TAS levels were significantly lower (p < 0.01) compared with the control group. CONCLUSIONS: Patients with OSAS have increased systemic oxidative stress and reduced levels of circulating antioxidant enzymes. Oxidative stress appears to be an underlying condition associated with OSAS.

Role of methylprednisolone in the prevention of postpericardiotomy syndrome after cardiac surgery.

OBJECTIVE: Postpericardiotomy syndrome (PPS) occurs in 10-40% of patients after cardiac operations. Pericardial effusions and tamponade occurring > 7 days after surgery are usually related to PPS and remain an important cause of cardiac surgery-related morbidity and mortality; therefore, preventing PPS is important. Colchicine affords safe and efficacious protection against PPS and related complications. However, the roles of corticosteroids and nonsteroidal anti-inflammatory drugs in PPS prevention remains unclear. This study aimed to determine whether the intraoperative use of single-dose methylprednisolone can effectively prevent PPS. PATIENTS AND METHODS: This retrospective study included 100 patients undergoing elective coronary artery bypass grafting (CABG) who received a single intraoperative dose of 1 mg/kg methylprednisolone. A further 100 patients undergoing CABG, who were not given methylprednisolone, comprised the control group. The presence and severity of pericardial effusion was determined by echocardiography, with chest X-ray used to assess pleural effusion. RESULTS: PPS occurrence and pericardial effusion occurrence were significantly lower in patients who received methylprednisolone (p = 0.02 and p = 0.007 respectively). Although the differences were not statistically significant, pericardial and pleural effusions were more severe in the control group than in the methylprednisolone group. Logistic regression analysis demonstrated that methylprednisolone administration was independently associated with prevention of PPS (OR 0.8, 95% CI 0.25-0.91, p <  0.026). CONCLUSIONS: Intraoperative, single-dose methylprednisolone may confer protection against PPS in patients undergoing CABG.

Value of the neutrophil-to-lymphocyte ratio in predicting post-pericardiotomy syndrome after cardiac surgery.

OBJECTIVE: Post-pericardiotomy syndrome (PPS) occurs in 10-40% of patients after cardiac surgery. PPS is considered an autoimmune phenomenon. The neutrophil-to-lymphocyte ratio (NLR) is a novel inflammatory marker that is associated with various cardiovascular diseases. Studies have reported that the NLR increases in certain autoimmune diseases. This study examined whether the NLR is helpful to predict the occurrence of PPS after elective on-pump coronary artery bypass graft (CABG) surgery. PATIENTS AND METHODS: The records of patients who underwent elective first-time on-pump CABG were reviewed retrospectively. In total, 72 patients with PPS were included in the study, and 100 patients who did not develop PPS were included as the control group. Peripheral blood samples collected preoperatively and on postoperative day 1 were used to calculate the NLR. RESULTS: No differences in preoperative white blood cell (WBC) count, neutrophil count, lymphocyte count, or NLR were observed between the patients with PPS and the control group. The WBC (p < 0.001) and neutrophil counts (p < 0.001) and NLR (p = 0.01) were significantly higher during the postoperative period in patients with PPS than in the control group. A receiver operating characteristic curve analysis showed that the postoperative NLR predicted PPS with 60% sensitivity and 59% specificity (area under the curve, 0.61; 95% confidence interval [CI], 0.51-0.70; p = 0.017), using a cut-off of 8.34. The postoperative WBC count (odds ratio [OR], 1.6; 95% CI, 1.36-2.03; p < 0.001) and NLR (OR, 3.3; 95% CI, 1.56-7.01; p = 0.002) were independently associated with PPS. CONCLUSIONS: The postoperative NLR may be useful to predict the development of PPS in patients undergoing on-pump CABG.

Inhibition of hemin-induced hemolysis by desferrioxamine: binding of hemin to red cell membranes and the effects of alteration of membrane sulfhydryl groups.

Hemin binds to red cell membranes during hemin-induced hemolysis but the precise mechanism of hemolysis has not been characterized. Desferrioxamine (DFO), an iron chelator, inhibited hemin-induced hemolysis. DFO partially prevented hemin binding to red cell membranes and partially removed previously bound hemin. Glutathione, an intracellular sulfhydryl compound, also inhibited hemin-induced hemolysis but was only about one tenth as potent as DFO. Decrease of membrane sulfhydryl groups by treatment of cells with either N-ethylmaleimide (NEM) or diamide (azodicarboxylic acid bis [dimethylamide]) enhanced hemin-induced hemolysis. Enhancement of hemin-induced hemolysis by NEM and diamide and inhibition of hemolysis by DFO were independent with no evidence of synergism or interference between the two processes. Red cell membranes were saturated with hemin at approximately 75 nmol per mg protein. DFO decreased the hemin saturation level to 25 nmol per mg protein. In the presence of DFO, hemin was bound as the DFO-hemin complex since membranes preferentially removed DFO-hemin complexes from mixtures of complexed and free hemin while free DFO was not bound by the membranes. Access to the inner surface of the membrane was required for binding of the DFO-hemin complex since DFO completely prevented hemin binding in intact cells but not in cells undergoing hemolysis or red cell ghosts. Approximately 50 x 10(6) molecules of hemin were bound to the membrane of one red cell following hemin-induced hemolysis.

t-butyl hydroperoxide-induced perturbations of human erythrocytes as a model for oxidant stress.

Erythrocytes were incubated with t-butyl hydroperoxide in the presence and absence of hemoglobin as a model system for oxidative stress and the alterations in the structure and integrity of the membranes were investigated. The results showed that in the presence of hemoglobin a significant modification in the membrane surface charge was induced but no such alteration was observed in peroxidized hemoglobin-free membranes. As increased hemoglobin oxidation occurred in the erythrocytes, membrane lipid peroxidation diminished, suggesting a protective role for methemoglobin in t-butyl hydroperoxide-induced lipid peroxidation. Electrophoresis on polyacrylamide gels showed modification of the cytoplasmic protein region but no high molecular weight aggregates formed at the concentrations of the hydroperoxide used in this work. The results suggest that the t-butyl hydroperoxide/normal erythrocyte system seems to be an instructive model for membrane perturbations characteristic of oxidative disorders.

The relative levels of alpha 2-, alpha 1-, and zeta-mRNA in HB H patients with different deletional and nondeletional alpha-thalassemia determinants.

We have analyzed the alpha 2/alpha 1-, alpha/beta-, zeta/(alpha + zeta)-mRNA ratios in the retic-ulocytes of 40 patients with Hb H disease. 21 patients had deletional Hb H disease (- -/- alpha), namely combinations of one of four types of alpha-thal-1 (MED-I, MED-II, -(alpha)20.5, SEA) and one of two types of alpha-thal-2 (-3.7 or -4.2 kb); 13 had Hb H disease because of combinations of one of these alpha-thal-1 deletions with either a 5 nt deletion at the 5' splicing site of IVS-I, or a terminating codon mutation (Hb CS), or a poly(A) mutation, and six were homozygous for either a poly(A) mutation or the 5 nt deletion. Significant differences were observed between the deletional types (- -/- alpha; alpha 2/alpha 1 ratio of zero; alpha/beta ratio of approximately 1) and non-deletional types (- -/alpha T alpha; alpha 2/alpha 1 ratio of 0.05-0.3 for those with T = the 5 nt deletion or the terminating codon mutant, and approximately 1.0 for those with T = a poly(A) mutation; alpha/beta ratio in all types of approximately 0.7). Comparable data were found for the nondeletional alpha-thal-2 homozygotes. The noted differences were highly significant and the determination of the two ratios may be diagnostically of considerable value. The low alpha 2/alpha 1-mRNA ratio in the two patients with - -/alpha-5nt alpha and the one patient with alpha-5nt alpha/alpha-5nt alpha indicates the presence of minute amounts of alpha 2-mRNA; apparently splicing at the donor site is greatly impaired by this deletion but not eliminated. The high alpha 2/alpha 1-mRNA ratio in the four patients with - -/alpha PA-2 alpha and the five patients with alpha PA-1 alpha/ alpha PA-1 alpha (PA-1 and PA-2 are poly(A) mutations) is due to the presence of an elongated alpha 2-mRNA which uses an alternate location as polyadenylation site. The relative levels zeta-mRNA varied considerably; the highest levels were found in patients with the -(alpha)20.5/-alpha or - -SEA/-alpha deletional types but not in those with the -(alpha)20.5/alphaPA-2 alpha, -(alpha)20.5/alpha-5nt alpha, or - -SEA/alphaCS alpha nondeletional types. No definitive explanation can be given for these differences; perhaps certain sequences that are part of some of the alpha-thal-1 deletions are important for the suppression of the zeta-globin gene.

Assessment of the ear and otoacoustic emission findings in fibromyalgia syndrome.

OBJECTIVE: We aimed to assess otoacoustic emission (OAE) findings in fibromyalgia (FM) syndrome. METHODS: Thirty-two ears of 16 female patients with FM syndrome and 30 ears of 15 healthy female controls were also included in the study. Pure tone audiometry, speech discrimination testing, tympanometry and otoacoustic emission testing (both transiently evoked and distortion product) were performed. RESULTS: There was no significant difference between the pure tone hearing results of the patients and controls (p > 0.05). There was no significant difference between the distortion-product-otoacoustic emission results of the patients and controls. Audiologic findings of the patients with and without otologic symptoms were not significantly different than controls (p > 0.05). CONCLUSION: Although FM patients generally have subjective symptoms related to ear, clinical or laboratory assessments usually fail to find out any objective finding related to these subjective symptoms. The otologic functions seem spared in FM syndrome.

Desferrioxamine protects human red blood cells from hemin-induced hemolysis.

Hemin binding to red cell membranes, its effect on red cell hemolysis, and it interaction with desferrioxamine (DFO) in these processes were investigated. DFO interacted with hemin via the iron moiety. Blockage of the binding groups in DFO prevented interaction of DFO with hemin, implying the importance of the hydroxamic acid groups in DFO-hemin interactions. Since hemolysis is a result of hemin association with the membrane components, its binding in the presence and absence of DFO was studied. DFO strongly inhibited hemin-induced lysis in a concentration-dependent manner. With 50 microM hemin, 1 mM DFO completely inhibited lysis. Preincubation of ghost membranes with DFO (1 mM) inhibited binding of hemin (50 microM) to membranes by 42%. After ghost membranes were preincubated with hemin (50 microM), the addition of DFO (1 mM) removed 20% of the membrane-bound hemin. It is suggested that DFO may have an important role in alleviating the hemin-induced deleterious effects on the red cell membrane, especially in hemolytic anemias associated with unstable, autoxidized hemoglobins.

The interactions of desferrioxamine and hydroxypyridone compounds with haemoglobin and erythrocytes.

The iron chelator desferrioxamine has been applied in many studies of pathological states by several investigators. The resulting decreases in cellular and tissue damage have been interpreted as an indication of the involvement of iron-mediated radical species. Although the nature and location of the iron species have not been identified, the assumption has often been made that desferrioxamine is able to enter cells. This paper reports investigations of the ability of desferrioxamine to cross the erythrocyte membrane in comparison with that of specific hydroxypyridone iron chelators by assessing their interaction with haemoglobin.

Management of incus long process defects: incus interposition versus incudostapedial rebridging with bone cement.

OBJECTIVE: This study aimed to compare the hearing results of incus interposition and bone cement ossiculoplasty in patients with incus long process defects. MATERIALS AND METHODS: Ninety-nine patients with incus long process defects were included. Incus interposition was performed in 49 patients (group 1) and bone cement ossiculoplasty was performed in 50 patients (group 2). Group 1 included 29 female and 20 male patients, with a mean age ± standard deviation of 29.43 ± 12.5 years (range, 8­58 years). Group 2 comprised 32 female and 18 male patients, with a mean age ± standard deviation of 29.1 ± 14.89 years (range, 8­67 years). RESULTS: The mean hearing gain ± standard deviation was 15.2 ± 9.01 dB in group 1 and 19.36 ± 9.08 dB in group 2. Hearing gain was significantly greater in the bone cement group than in the incus interposition group (p = 0.0186). Successful hearing results (i.e. air­bone gap < 20 dB) were achieved by 63.2 per cent of group 1 patients and 78 per cent of group 2 patients. CONCLUSION: Incus interposition and bone cement ossiculoplasty are safe and reliable methods with which to manage incus long process defects. Bone cement ossiculoplasty gives a greater hearing gain in appropriate cases.

ICSH recommendations for the measurement of haemoglobin A2.

Although DNA analysis is needed for characterization of the mutations that cause ß-thalassaemia, measurement of the Hb A(2) is essential for the routine identification of people who are carriers of ß-thalassaemia. The methods of quantitating Hb A(2) are described together with pitfalls in undertaking these laboratory tests with particular emphasis on automated high-performance liquid chromatography and capillary electrophoresis.

ICSH recommendations for the measurement of haemoglobin F.

Measurement of the Haemoglobin F in red cell haemolysates is important in the diagnosis of 뫧 thalassaemia, hereditary persistence of fetal haemoglobin (HPFH) and in the diagnosis and management of sickle cell disease. The distribution of Hb F in red cells is useful in the diagnosis of HPFH and in the assessment of feto-maternal haemorrhage. The methods of quantifying Hb F are described together with pitfalls in undertaking these laboratory tests with particular emphasis on automated high-performance liquid chromatography and capillary electrophoresis.

Molecular heterogeneity of beta-thalassemia in the United Arab Emirates.

The beta-thalassemia alleles in 313 national patients of the United Arab Emirates (UAE) have been characterized using PCR-based DNA-diagnostic techniques including DNA sequencing. A total of 212 patients had homozygous beta-thalassemia and the remaining 101 were compound heterozygotes. More than half of the patients were homozygous for the IVS-I-5 (G-->C) mutation followed by the sickle cell gene. The latter accounted for 25% of the chromosomes. In terms of frequency, five beta-thalassemia mutations; IVS-I-5 (G-->C), betaS, -25 bp del, Cd 8/9 (+G) and IVS-II-1 (G-->A) accounted for 83% of the alleles. In addition, 427 expatriate patients were studied: 256 with homozygous beta-thalassemia and 171 were compound heterozygotes. In both the UAE nationals and expatriates, the beta-thalassemia mutations and their frequency followed a similar trend. Our results indicate that the frequency of beta-globin gene defects including beta-thalassemia, sickle cell gene (betaS) and abnormal hemoglobins is significantly increased and poses a major public health problem in the UAE. The number of homozygous patients strongly suggests a high degree of consanguinity among the UAE nationals. With 50 different beta-thalassemia alleles, UAE is arguably the most heterogeneous population in the world. The diversity of these mutations reflects the historical admixture of genes and their migration from different areas in the region. Our data strongly suggest the need for a comprehensive thalassemia control program and provides a basis for population screening, genetic counseling and prenatal diagnosis.