Erythrocyte Osmotic Fragility Test Research Articles

In Vitro Studies on the Effects of Aqueous Extracts of Syzygium Aromaticum Linn. (Cloves) and Zingiber Officinale Roscoe (Ginger) on Erythrocyte Osmotic Fragility in Sickle Cells

Sickle cell disease is a genetically inherited blood disease that is characterized by the production of abnormal erythrocytes, shaped like a sickle. Definite cure for sickle cell disease is yet to be established, therefore, palliative methods such as antioxidant agents which reduce occurrence of intravascular haemolysis are employed. Naturally occurring antioxidants are found in Syzygium aromaticum Linn. (Clove) and Zingiber officinale (ginger) as documented by previous researches are therefore tested on the erythrocyte osmotic fragility of sickle cell red blood cells (RBC). Aqueous extracts of clove and ginger were obtained by maceration and antioxidant activity of the extracts was determined by 2, 2,-diphenyl-1-picryl-hydrazyl (DPPH) using ascorbate as standard. Blood samples from twenty five sickle cell disease subjects were collected and divided into five groups. Group one was control, groups two and three were incubated with 1mg/ml and 10mg/ml of clove extract respectively, while groups four and five were incubated with 1mg/ml and 10mg/ml of ginger extract respectively. Erythrocyte osmotic fragility was determined using graded series of hypotonic Sodium Chloride (NaCl) solutions of concentrations ranging from 0.1% to 0.9%. Analysis of Variance (ANOVA) and Turkey test was used to analyze data and test of significance was applied at p?0.05. The results revealed the presence of phenols, alkaloids, flavonoid and tannins in both clove and ginger extracts; glycosides were present in ginger but absent in clove. Antioxidant at low concentration of 50µg/ ml showed percentage inhibition of clove and ginger were 67.43% and 11.87%, respectively, and that of ascorbate was 20.15%. At high concentration of 250µg/ml, clove and ginger had percentage inhibition of 93.8% and 81.18% respectively, while ascorbate had 84.06%. Erythrocyte osmotic fragility test results showed complete haemolysis at 0.1% NaCl concentration in all groups. At 0.2% NaCl concentration, percentage haemolysis of the group treated with 10mg of clove 69.12 ± 0.05, was significantly lower (p?0.05) than the control (98.12 ± 0.05), while the group treated with 10mg ginger extract showed 98.02 ± 0.04 which is not significantly lower (p?0.05) than that of the control. At 0.5% NaCl concentration, percentage haemolysis of groups treated with 10mg clove extract and 10mg ginger extract were 8.400.18 and 20.42 ± 0.18, respectively, which were significantly lower (p?0.05) than that of the control group (45.90 ± 0.10). The groups treated with 1mg clove extract and 1mg ginger extract showed percentage haemolysis values of 38.04 ± 0.10 and 30.02 ± 0.10 respectively at 0.5% NaCl concentration which were significantly lower (p?0.05) than the control group (45.90 ± 0.10). Clove showed higher antioxidant activity than ginger. Both plants also demonstrated a capacity for maintaining erythrocyte membrane stability, with clove being better at lowering erythrocyte fragility than ginger.

Effects of crude methanol extract of Adansonia digitata fruit pulp on Naja nigricollis venom-induce toxicity in Wistar rats.

This study evaluated the effects of Crude Methanol Extract of Adansonia digitata Fruit Pulp on Naja nigricollis Venom-Induce Toxicity in Wistar rats. A. digitata was extracted using 70% methanol and median lethal dose (LD50) of both the extract and venom were determined using the up-and-down method. Sixty Wistar rats were randomly assigned into 10 groups of 6 rats each and were administered with normal saline, venom only, venom+antivenom, 125mg/kg, 250mg/kg and 500mg/kg crude methanol extract (CME) pre-envenomation, 125mg/kg, 250mg/kg and 500mg/kg CME post-envenomation, and venom+antivenom+250mg/kg CME, respectively. Blood samples were collected 8-h post-envenomation in EDTA and plain sample bottles. Erythrocyte osmotic fragility (EOF) test was carried out on the EDTA blood samples while serum washarvested and used for Malondialdehyde (MDA) and Superoxide Dismutase (SOD) assays. LD50 of the CME and venom was >5,000mg/kg and 0.889mg/kg, respectively. N. nigricollis-induced oxidative stress was evident in group B through increased % haemolysis, MDA and lowered SOD activities. The groups treated with antivenom only, 250mg/kg CME post-envenomation and antivenom +250mg/kg CME significantly (p<0.05) reduced EOF, MDA values and increased SOD. The CME revealed better ameliorative effect than protective via inhibition of EOF, MDA values and increased SOD activity. The CME when administered singly showed more ameliorative properties and the combination of CME with antivenom for protection was not as effective as when compared to single administration.

Genetic Deletion of Trace-Amine Associated Receptor 9 (TAAR9) in Rats Leads to Decreased Blood Cholesterol Levels.

In the last two decades, interest has grown significantly in the investigation of the role of trace amines and their receptors in mammalian physiology and pathology. Trace amine-associated receptor 9 (TAAR9) is one of the least studied members of this receptor family with unidentified endogenous ligands and an unknown role in the central nervous system and periphery. In this study, we generated two new TAAR9 knockout (TAAR9-KO) rat strains by CRISPR-Cas9 technology as in vivo models to evaluate the role of TAAR9 in mammalian physiology. In these mutant rats, we performed a comparative analysis of a number of hematological and biochemical parameters in the blood. Particularly, we carried out a complete blood count, erythrocyte osmotic fragility test, and screening of a panel of basic biochemical parameters. No significant alterations in any of the hematological and most biochemical parameters were found between mutant and WT rats. However, biochemical studies revealed a significant decrease in total and low-density lipoprotein cholesterol levels in the blood of both strains of TAAR9-KO rats. Such role of TAAR9 in cholesterol regulation not only brings a new understanding of mechanisms and biological pathways of lipid exchange but also provides a new potential drug target for disorders involving cholesterol-related pathology, such as atherosclerosis.

Effect of hydro-methanol stem bark extract of Burkea africana on erythrocyte osmotic fragility and haematological parameters in acetaminophen-poisoned rats

BackgroundBurkea africana is a widely used medicinal plant in folkloric medicine in many developing countries of the world. It is useful in the treatment of various ailments including hepatitis, jaundice, diarrhea, stomach aches, abscesses, oedema, epilepsy, bloody diarrhea, gonorrhea, syphilis, toothaches and poisoning. Nevertheless, there are little or no scientific evidence to substantiate this medicinal claim by traditional healers. Burkea africana stem bark was therefore, investigated for its protective or stabilizing effect on erythrocyte membrane in acetaminophen-treated rats. B. africana stem bark was extracted using 80% methanol. Erythrocyte stabilizing effect was studied using erythrocyte osmotic fragility (EOF) test. Thirty (30) male rats were randomly assigned into five (5) groups of six (6) rats each. Groups 1 and 2 served as normal control and negative control (acetaminophen-treated group) respectively. Groups 3, 4 and 5 were pretreated with methanol stem bark extract of Burkea africana (MSBEBA) at doses of 200, 400 and 600 mg/kg body weight respectively once daily for seven (7) days. Blood samples were collected from the animals in all the groups on the 8 day for evaluation of packed cell volume, haemoglobin, red blood cell, white blood cell counts, and differential white blood cell count as well as erythrocyte osmotic fragility.ResultsThe erythrocyte osmotic fragility test showed that there was a significantly (p < 0.05) low percentage hemolysis in the groups pre-treated with the extract when compared with the negative control. The percentage hemolysis was least at 600 mg/kg body weight of the extract. There was also a significant (p < 0.05) increase in the packed cell volume, haemoglobin, red blood cell count at all the doses of the extract used. Neutrophils were significantly (p < 0.05) decreased while lymphocytes were significantly increased in the groups administered MSBEBA 400 and 600 mg/kg body weight.ConclusionMethanol stem bark extract of Burkea africana had protective effect on the red blood cells and also improved haematological parameters. This indicates that Burkea africana may be useful in the treatment of disease conditions that results in hemolytic anemia by stabilizing red erythrocyte membranes and enhancing erythropoiesis.

A review of the factors that influence erythrocyte osmotic fragility

Erythrocyte osmotic fragility is a laboratory test which evaluates the stability of the erythrocyte membrane to osmotic stress. The aim of this review is to highlight research findings on the intrinsic and extrinsic factors that influence erythrocyte osmotic fragility. The extrinsic factors include the type, ionic strength and pH of incubation media, type of anticoagulant and storage time of the blood, ambient temperature, drugs, medicinal plant extracts, xenobiotics, chemical agents; whereas intrinsic factors are age, sex, breed, species, pregnancy, lactation and genetic factors. Membrane composition, ion transports, aquaporin action, lipid peroxidation, and eryptosis of erythrocytes are involved in the variability of osmotic fragility. Increased osmotic fragility and improved osmotic stability of erythrocytes are pathophysiological phenomena that require appropriate interpretation in research or clinical investigation and the understanding of the factors affecting osmotic fragility will aid in the laboratory assessment of conditions related to erythrocytes where erythrocyte osmotic fragility test is used. Keywords: Erythrocyte, Extrinsic factors, Intrinsic factors, Osmotic fragility, Osmotic stability

Effect of Doxorubicin and Some Boron Compounds on Erythrocyte Fragility In Rats

Objective: Doxorubicin is a potent antineoplastic agent used in chemical treatment of cancer. However due to their cardiotoxic effects, its use is limited and currently subject for extensive research. Cardiomyopathy caused by doxorubicin still remains as a major concern for this potent drug. This study was aimed to contribute to this issue which needs novel preventive treatment for this side effect. Materials and Methods: Boron and boron containing molecules are subject of medical research due to their properties such as antioxidant nature. They are tested in various diseases and experimental setups. In this study Boric acid, Potassium tetraborate, Amonium biborat tetrahidrat was given to male rats at 10 mg/kg/day for 6 weeks. All study groups (n=8 each) received Doxorubicin and Boron containing compounds via intraperitoneal route. Following 6 weeks blood was withdrawn and erythrocyte osmotic fragility test was applied. Results: Erythrocyte fragility values of all doxorubicin containing groups increases and become significant at 0.5, 0.6, 0.7 and 0.8% NaCl concentrations (p<0.05). Among doxorubicin groups no significant difference was observed. Results of this study suggests that doxorubicin increases erythrocyte osmotic fragility and boron containing molecules are not sufficient to recover this untoward effect on erythrocytes at the applied dosage. Conclusion: Possible mechanisms of this result and testing in a dose dependent manner can be tested in future studies.

Protective Effect of Resveratrol Co-Administration with Cholesterol Diet on Erythrocyte Osmotic Fragility and Malondialdehyde Concentration in Rabbits

The aim of the experiments was to investigate the protective effect of resveratrol co-administration with cholesterol diet on erythrocyte osmotic fragility (EOF) and malondialdehyde (MDA) concentration in rabbits. Thirty rabbits divided into six group of five animals (n = 5) each were used for the experiment: Group 1 = normal control (C), group 2 = cholesterol diet (CD) only, group 3 = resveratrol 200 mg/kg (R200), group 4 = resveratrol 400 mg/kg (R400), group 5 = CD + R200 and group 6 = CD + R400. Eight weeks after the treatment period, blood sample of about 5 ml (3 ml in EDTA bottle for erythrocyte osmotic fragility (EOF) test and 2 ml in plane tube for extraction of serum for malondialdehyde concentration (MDA) were drawn from the heart of each sacrificed animal from all group by cardiac puncture. At 0.45% of NaCl concentration, the percentage haemolysis of 100% obtained in the CD group was considerably higher than the value of 59% recorded in the CD + R400 mg/kg and 30% haemolysis recorded for normal control group. Increases in haemolysis were indicated on the point in the graph presented. The MDA concentration obtained in the CD group rabbits (2.64±0.18 nmol/ml) was higher compared to those of CD + R200 and CD + R400 with a value of 1.70±0.14 nmol/ml and 1.64±0.12 nmol/ml respectively. It is concluded that CD increased haemolysis and MDA concentration in rabbits, ameliorated by resveratrol administration.

Effect of 16 pure hydrocarbons on the stabilization and lysis of fish (mudskipper: Boleophthalmus dussumieri) erythrocytes

The in vitro effects of polycyclic aromatic hydrocarbons (PAHs) on erythrocyte membrane stability of the mudskipper (i.e., Boleophthalmus dussumieri) were tested by using field concentrations, acute and chronic potency divisor concentrations. This was achieved by studying their lytic or antilytic effects on fish erythrocytes in critical hypotonic saline media. The interaction of PAHs acute potency divisor concentrations with mudskipper erythrocyte causes dramatic changes in the structure of the membrane. A significant difference (p<0.05) was found between the control and treatment groups of mudskipper erythrocyte exposed to acute potency divisor concentrations. No significant difference (p>0.05) was observed between the control and the treatment groups of mudskipper erythrocyte exposed to field concentrations. The results showed that chronic potency divisor concentrations of PAHs protect mudskipper erythrocyte against osmotic hemolysis. Our results could be extended to the use of Erythrocyte Osmotic Fragility (EOF) test as a biochemical marker of membrane toxicity in marine pollution biomonitoring. However, results showed that membrane stability is not an appropriate biomarker for PAHs pollution after short exposure duration.

Dietary taurine can improve the hypoxia-tolerance but not the growth performance in juvenile grass carp Ctenopharyngodon idellus

This study was conducted to evaluate the effects of dietary taurine, as a feed additive, on the hypoxia-tolerance and growth performance of the juvenile grass carp Ctenopharyngodon idellus, one of the most important and intensively cultured freshwater fish, with the largest production in China. Graded levels of taurine (0, 0.5, 1, 1.5, 2 and 2.5 g kg(-1) dry diet) were fed to grass carp juveniles (mean weight: 5.26 ± 0.03 g) for 8 weeks. The survival time during acute hypoxia increased as dietary levels of taurine increased, with the highest dose of taurine resulting in the best acute hypoxia-tolerance. The erythrocyte osmotic fragility in grass carp was significantly improved when dietary taurine level was at least 1.5 g kg(-1) diet and can be improved much more when dietary taurine level was up to 2.5 g kg(-1) diet. A significant correlation between hemolysis rate of the erythrocyte osmotic fragility test and the survival time of acute hypoxia (r = -0.873, P = 0.023 < 0.05) strongly suggested that the biomembrane stabilization function of taurine may contribute to its role of enhancing acute hypoxia-tolerance in grass carp. Dietary taurine cannot improve growth performance of grass carp, but it can increase the value of mesenteric fat index, indicating that dietary taurine influences the lipid metabolism. This study provides valuable information to improve hypoxia-tolerance of grass carp.

Immunotoxicity of Copper Alginate Fibers in Guinea Pigs and Mice

The relation between copper alginate fibers and immunotoxicity in animals was studied by dividing guinea pigs and mice into control groups and experimental groups. Varied weights of fibers were subcutaneously embedded in the experimental groups, whereas the control groups were operated on simulatively. Morphology analysis, erythrocyte osmotic fragility (EOF) test, direct plaque-forming cell (PFC) assay, quantitative hemolysis spectrophotometry (QHS) assay, macrophages phagocytosis assay, and pathology analysis were used to examine morphology, microstructure, and immunotoxicity. With increasing doses of copper alginate fibers, the EOF of experimental groups increased in contrast with the control group. Moreover, the antibody level decreased based on the results of the PFC and QHS assays, and macrophages phagocytosis descended in relation to dose. However, the immune functions were weakened without time dependence. According to pathologic photographs, the partial organs were damaged, implying bad histocompatibility. Hence, copper alginate fiber is proved to be a harmful material for medical devices.

Erythrocyte osmoticfragility test and determination of hemoglobin A for screening neonatal β thalassemia

：Objective To exploreerythrocyte osmotic fragility test and determination of hemoglobin A for screeningneonatal β thalassemia and improve thediagnostic rate of slight β-thalassemia.Methods Cordblood samples were obtained from the full-term newborns in my hospital from January 2009to December 2010. The erythrocyte fragility was detected by erythrocyte osmotic fragilitytest, and hemoglobin A was analyzed quantitatively using the automatic system ofhemoglobin electrophoresis. Results Of 7023 newborns, 6834 were normal and 189 weresuspected to have β thalassemia. 159 wereconfirmed as β thalassemia through geneticanalysis, with a detection rate of 84.13%. A significant difference was found between thenomal newborns and the suspected newborns (P＜0.01). onclusions Cord blooderythrocyte osmotic fragility test and determination of hemoglobin A, in combination withhemoglobin analysis on pateral and maternal family, can be used as an important indicatorfor screening neonatal β thalassemia.

Sensitivity and Specificity of Simple Erythrocyte Osmotic Fragility Test for Screening of Alpha-Thalassemia-1 and Beta-Thalassemia Trait in Pregnant Women

Sensitivity and Specificity of Simple Erythrocyte Osmotic Fragility Test for Screening of Alpha-Thalassemia-1 and Beta-Thalassemia Trait in Pregnant Women

Sensitivity and Specificity of Simple Erythrocyte Osmotic Fragility Test for Screening of Alpha-Thalassemia-1 and Beta-Thalassemia Trait in Pregnant Women

Aims: To evaluate the validity of new simple qualitative osmotic fragility test (simple OF) as a screening test in predicting thalassemia trait (alpha-thalassemia-1 and beta-thalassemia). Methods: This diagnostic test study was conducted on non-anemic pregnant women attending antenatal care clinic, Maharaj Nakorn Chiang Mai Hospital, during September 2007, and June 2008. Blood samples were collected from 477 singleton pregnancies with no obvious medical complication such as iron deficiency anemia. Simple OF was performed in the same day, using 0.45% glycerin saline solution instead of saline solution. Quantitative HbA2 test and PCR (SEA type) were performed as gold standard to confirm the diagnosis of beta-thalassemia trait and alpha-thalassemia-1 trait, respectively. The main outcome measures included sensitivity, specificity, positive and negative predictive value of simple OF. Results: The simple OF test had very high sensitivity of 100%, specificity of 73%, positive and negative predictive value of 35, and 100%, respectively. Conclusion: The new simple OF test (using 0.45% glycerin) has high sensitivity in detection of alpha-thalassemia-1 trait or beta-thalassemia trait and due to its simplicity, rapidity, availability and very low cost it may, therefore, be considered as a screening test in a large-scale population.

Erythrocyte Osmotic Fragility Test for Screening of Alpha-thalassemia-1 and Beta-thalassemia Trait in Pregnancy

Erythrocyte Osmotic Fragility Test for Screening of Alpha-thalassemia-1 and Beta-thalassemia Trait in Pregnancy

Microcirculation disturbance affects rats with acute severe pancreatitis following lung injury

To study the effects of microcirculation disturbance (MD) on rats with acute severe pancreatitis (ASP). We developed ASP rat models, and anatomized separately after 1, 3, 5, 7, and 9 h. We took out blood and did hemorrheologic examination and erythrocyte osmotic fragility test, checked up the water content, capillary permeability, and genetic expression of intercellular adhesion molecule-1 (ICAM-1) in lung tissues, examined the apoptosis degree of blood vessel endothelium while we tested related gene expression of Bax and Bcl-2 in lung tissues. We did the same examination in control group. The viscosity of total blood and plasma, the hematocrit, and the erythrocyte osmotic fragility were all increased. Fibrinogen was decreased. The water content in lung tissues and capillary permeability were increased. Apoptosis degree of blood vessel endothelium was increased too. ICAM-1 genetic expression moved up after 1 h and reached its peak value after 9 h. MD plays an important role in ASP following acute lung injury (ALI). The functional damage of blood vessel endothelium, the apoptosis of capillary vessel endothelium, WBC edging-concentration and the increasing of erythrocyte fragility are the main reasons of ALI.

Erythrocyte osmotic fragility test for screening of alpha-thalassemia-1 and beta-thalassemia trait in pregnancy

Objectives: To evaluate the sensitivity and specificity of osmotic fragility test (OFT) as a screening test in predicting the severe thalassemia trait (α-thalassemia-1 & β-thalassemia). Methods: A descriptive analysis and diagnostic test of non-anemic pregnant women attending antenatal care clinic, Maharaj Nakorn Chiang Mai, during April, and July 2002 was made. Blood samples were collected from 446 singleton pregnancies with no obvious medical complication such as iron deficiency anemia. OFT was performed in the same day, using 0.45% glycerin saline solution and the cut-off value of less than 60% was used for an abnormal test. Quantitative HbA2 test and PCR (SEA type) were done as a gold standard to confirm the diagnosis of β-thalassemia trait and α-thalassemia-1 trait, respectively. Results: The main outcome measures were sensitivity, specificity, positive and negative predictive value of OFT. If the OFT cut-off value of less than 60% was considered positive, the test had a sensitivity, specificity, positive and negative predictive value of 97.6%, 72.9%, 33.6%, and 99.5%, respectively. Conclusion: OFT has high sensitivity in detection of α-thalassemia-1 trait or β-thalassemia trait and due to its simplicity with very low cost it may, therefore, be considered as a screening test in a wide population.

Erythrocyte osmotic fragility test as the measure of defence against free radicals in rabbits of different age.

Peroxidation of the unsaturated bonds of membrane lipids increases fragility and cellular lysis of red blood cells. Erythrocyte susceptibility to the free radicals (peroxyl radicals) generated in vitro by 2,2'-azo-bis(2-amidinopropane) hydrochloride (AAPH) was evaluated and expressed as 50% maximal haemolysis time (HT50) in 3 groups of rabbits of different age. Erythrocytes of 1.5-month-old rabbits were more sensitive to free radicals than those of 3.5- and 6-month-old ones. In the three groups, significant negative correlation (r = -0.8 to -0.98) between the lipid peroxidation rate (thiobarbituric acid reactive substances; TBARS concentration) in blood plasma and the erythrocyte resistance to free radicals was found. This result suggests that the plasma antioxidant defence system is interrelated with that of the red blood cells and that the erythrocytes can be a good model for studies of oxidative stress. The simple haemolysis test reflecting the free radical defence can be useful for evaluating the antioxidant properties of various compounds.

Erythrocyte osmotic fragility test as the measure of defence against free radicals in rabbits of different age

Erythrocyte osmotic fragility test as the measure of defence against free radicals in rabbits of different age

PRENATAL DIAGNOSIS OF β-THALASSEMIA MAJOR BY HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY ANALYSIS OF HEMOGLOBINS IN FETAL BLOOD SAMPLES

In Thailand and adjacent countries, most of the β-thalassemia genes are β0-thalassemia mutations that prevent the production of Hb A. We propose the quantitation of the Hb A fraction in fetal blood in the mid-trimester of pregnancy by automated high performance liquid chromatography as a reasonable prenatal diagnostic method to be applied in areas with limited laboratory facilities. Forty pregnant women at risk of delivering a child with β-thalassemia major were identified using an erythrocyte osmotic fragility test and quantitation of Hb A2. Cordocentesis was performed at the gestational age of 18–22 weeks and fetal blood was analyzed for hemoglobin fractions by automated high performance liquid chromatography. The β-globin gene mutations were characterized by β-globin gene sequencing. The 4 bp deletion at codons 41/42 (−TTCT) was the most frequent of the 40 β-thalassemia mutations observed (20/40 = 50%), followed by the splice site mutation IVS-I-1 (G → T) (7/40 = 17.5%), the nonsense mutation at codon 17 (A → T) (7/40 = 17.5%), the nonsense mutation at codon 35 (C → A) (3/40 = 7.5%), and the β+ -thalassemia promoter mutation at −28 (A → G) (3/40 = 7.5%). High performance liquid chromatography revealed nine fetuses which had only Hb F and no Hb A. All were homozygotes or compound heterozygotes for β0-thalassemia mutations. In the remaining 31 fetuses, a Hb A peak was present in the chromatograms. One fetus with 0.5% Hb A was a compound heterozygote for the −28 (A → G) and codons 41/42 (−TTCT) mutations. In the remaining 30 fetuses, the Hb A values ranged between 0.8 and 7.4%. Twenty of these, with a Hb A concentration of 1.82 ± 0.49% (range 0.8–2.8%), were β-thalassemia heterozygotes. The remaining 10 fetuses had Hb A values of 4.89 ± 1.47% (range 2.9–7.4%) and normal β-globin genes. The absence of Hb A in homozygotes or compound heterozygotes for β0-thalassemia mutations and the presence of measurable amounts of Hb A in heterozygotes and normal homozygotes, permits the diagnosis of fetuses expected to develop postnatal β-thalassemia major.

Screening for Alpha-Thalassemia-1 Heterozygotes in Expecting Couples by the Combination of a Simple Erythrocyte Osmotic Fragility Test and a PCR-Based Method

Objective: To develop a simple method for the prospective identification of couples at risk of homozygous α-thalassemia-1 (Hb Bart’s hydrops fetalis) in pregnancy. Methods: Antenatal care (ANC) women and their husbands were analyzed using a simple erythrocyte osmotic fragility (EOF) test and a PCR-based method for the detection of the mutation leading to α-thalassemia-1 of the Southeast Asian type (SEA). Results: Heterozygosity for the α-thalassemia-1 (SEA) deletion was found to correlate with an EOF value <60%. For a prospective screening, ANC women and their husbands are analyzed with the EOF test and only those having a value <60% were further checked by PCR. Of 2,769 cases analyzed during a 6-month period, 24 couples in which both partners are heterozygotes could be identified for genetic counseling and prenatal diagnosis. The application of the EOF test decreased the workload for PCR by ∼80%. Conclusion: Prospective screening for α-thalassemia-1 (SEA) heterozygotes in northern Thailand is becoming easier to realize by the combination of EOF test and PCR.