Differences in the serum metabolic profile to identify potential biomarkers for cyanotic versus acyanotic heart disease

BACKGROUND

Growth retardation, malnutrition, and failure to thrive are some of the consequences associated with congenital heart diseases. Several metabolic factors such as hypoxia, anoxia, and several genetic factors are believed to alter the energetics of the heart. Timely diagnosis and patient management is one of the major challenges faced by the clinicians in understanding the disease and provide better treatment options. Metabolic profiling has shown to be potential diagnostic tool to understand the disease.

OBJECTIVE

The present experiment was designed as a single center observational pilot study to classify and create diagnostic metabolic signatures associated with the energetics of congenital heart disease in cyanotic and acyanotic groups.

METHODS

Metabolic sera profiles were obtained from 35 patients with cyanotic congenital heart disease (TOF) and 23 patients with acyanotic congenital heart disease (ASD and VSD) using high resolution 1D 1H NMR spectra. Univariate and multivariate statistical analysis were performed to classify particular metabolic disorders associated with cyanotic and acyanotic heart disease.

RESULTS

The results show dysregulations in several metabolites in cyanotic CHD patients versus acyanotic CHD patients. The discriminatory metabolites were further analyzed with area under receiver operating characteristic (AUROC) curve and identified four metabolic entities (i.e. mannose, hydroxyacetone, myoinositol, and creatinine) which could differentiate cyanotic CHDs from acyanotic CHDs with higher specificity.

CONCLUSION

An untargeted metabolic approach proved to be helpful for the detection and distinction of disease-causing metabolites in cyanotic patients from acyanotic ones and can be useful for designing better and personalized treatment protocol.

Molecular diagnosis and genetic counseling for fragile X mental retardation

The fragile X syndrome is the most frequent cause of inherited mental retardation. It is caused by a dynamic mutation: the progressive expansion of polymorphic (CGG)n trinucleotide repeats located in the promoter region of the FMRI gene at Xq27.3. The cloning of the FMRI gene and the elucidation of the molecular basis of the fragile X syndrome is of great importance for the diagnosis and understanding of this unusual type of mutation. Although extensively studied, the mechanism behind the transition from stable normal (CGG)n alleles to the carrier state (an unstable premutation) and from premutation to mutation is partially understood. The clinical diagnosis of fragile X mental retardation (FXMR) is not possible as dysmorphic features are subtle. Molecular diagnosis by Southern Blot is the confirmatory test that makes carrier detection and prenatal diagnosis possible. As the risk of recurrence of FXMR is high in the family and carrier relatives, an identification of fragile X positive children, and offering carrier detection and prenatal diagnosis to the families is very important. It is possible by screening mentally retarded children and adults even if there is no family history of mental retardation or typical behavioral or physical features associated with the fragile X phenotype. In this review we have discussed the method for the diagnosis and counseling of the families. The complexities due to premutation and the variable severity of manifestations in carrier females need to be understood while counseling fragile X families.

Internet resources for the human geneticist

The Internet is a massive expanding body of information, which is likely to play a significant role for clinicians and researchers across the world. Since its inception in December 1969 the Internet has grown rapidly and is anticipated to expand 1,000% in the coming next few years. Various useful databases on human genetics are already in 'the Net' and many more are being added constantly. The future of human geneticist is in handling of information. In this review of Internet and compilation of important web site addresses we expect to stimulate and instruct human geneticists in navigating the Net. The list of web sites provided in this article is expected to facilitate their search.

The histopathology of chronic gastritis

Chronic gastritis is a multifactorial disorder thought to be influenced by bacterial and host genetic factors. Histopathological examination is the mainstay of diagnosis, however features like the presence of Helicobacter pylori are difficult to evaluate on biopsy. We evaluated 120 gastric antral biopsies using the revised Sydney system. The density of the inflammatory infiltrate, H pylori and mast cells were evaluated. It was seen that the presence of H pylori is strongly associated with an acute and a chronic inflammatory infiltrate. The presence of neutrophils on biopsy is strongly associated with the presence of H pylori and with the density and the grade of the chronic inflammatory infiltrate. The chronic inflammatory response is an intermediary between the acute inflammatory process and glandular atrophy. The lymphocytic infiltrate is also a precursor lesion of the lymphoid follicles. The presence of mast cells does not appear to be related to any of the other inflammatory parameters. The presence of one feature is a strong indicator for the presence of other inflammatory features.

Differential response of stress fibers and myofibrils to gelsolin

The actin-severing activity of human platelet gelsolin was analyzed on embryonic skeletal and cardiac myofibrils, and on stress fibers in non-muscle cells. These subcellular structures, although in all three cell types composed of contractile proteins arranged in sarcomeric units, were found to respond differently to gelsolin. The myofibrils in permeabilized myotubes or cardiac cells, as well as in living, microinjected muscle cells proved resistant to a wide concentration range of gelsolin. The same was found for the "mini-sarcomeres" which are seen in developing muscle cells. In contrast, stress fibers in microinjected fibroblasts or epithelial cells, as well as in permeabilized cells, were broken down rapidly by the platelet gelsolin. We conclude from these results that the mini-sarcomeres in embryonic myotubes and cardiac myocytes are not identical with stress fibers.

Clinical and molecular diagnosis of spinal muscular atrophy

The spinal muscular atrophies are a group of disorders characterized by flaccid limb weakness. It is necessary to differentiate these from other causes and identify the SMA variants. In classical SMA, majority of the patients shows homozygous deletion of the telomeric SMN gene (SMN1) on chromosome 5q. The availability of DNA analysis has allowed proper genetic counseling and prenatal diagnosis in the affected families. Application of newer techniques has enabled more accurate carrier detection. Our objective is to stress the variability in the clinical features and recent advances in the molecular diagnosis for SMA.

Genetic polymorphism of drug metabolizing enzymes (CYP2E1, GSTP1) and susceptibility to bladder cancer in North India

Glutathione-S-transferases (GSTs) are active in the detoxification of wide variety of endogenous or exogenous carcinogens and genetic polymorphisms of CYP2E1 and GSTP1 genes have been studied extensively to evaluate the relative risk of various cancers. In the present study, we examined associations with CYP2E1 and GSTP1 gene polymorphisms in sporadic bladder cancers from North Indian patients. The subjects were 106 bladder cancer (Ca-B) cases and 162 age-matched controls. The GSTP1 313 A/G polymorphism was determined by the PCR/RFLP method using peripheral blood DNA. Binary Logistic Regression Model was used for assessing differences in genotype prevalence and their associations between patient and the control group. We observed a non-significant association in Pst1 polymorphism of the CYP2E1 gene; though the A/G genotype (OR = 2.69, 95% CI=1.57- 4.59, P= 0.000) and G/G genotype (OR = 7.68, 95% CI=2.77- 21.26, P= 0.000) of the GSTP1 gene polymorphism alone or in combination with tobacco users were highly significant (OR=24.06; 95% CI: 4.80- 120.42; P =0.000) when compared to the controls. The results of our study demonstrated that the GSTP1 313 G/G polymorphism is a strong predisposing risk factor for bladder cancer in the North Indian population.

Genetics of gallstone disease

Gallstone disease is a complex disorder where both environmental and genetic factors contribute towards susceptibility to the disease. Epidemiological and family studies suggest a strong genetic component in the causation of this disease. Several genetically derived phenotypes in the population are responsible for variations in lipoprotein types, which in turn affect the amount of cholesterol available in the gall bladder. The genetic polymorphisms in various genes for apo E, apo B, apo A1, LDL receptor, cholesteryl ester transfer and LDL receptor-associated protein have been implicated in gallstone formation. However, presently available information on genetic differences is not able to account for a large number of gallstone patients. The molecular studies in the animal models have not only confirmed the present paradigm of gallstone formation but also helped in identification of novel genes in humans, which might play an important role in pathogenesis of the disease. Precise understanding of such genes and their molecular mechanisms may provide the basis of new targets for rational drug designs and dietary interventions.

Fighting cancer in the information age: the role of Internet

Cancer is a major health problem worldwide which is likely to assume alarming proportions in the next two decades. Communication and information have increasingly been considered important in helping people to cope with cancer. The arrival of Internet offers the opportunity to fundamentally reinvent medicine and health care delivery. Medical professionals can now use the Internet for continuing medical education, access latest medical information, for fast confirmation of diagnosis, exchange opinion on treatment strategies and in palliative care. Internet can provide cost-effective and timely ways to deliver a complex mix of interesting and high-quality information and expertise to cancer patients. Patients can also independently search the Internet to know about their illness and treatment options. However, of concern is the quality of information that is available in the 'Net'. Some Internet sites may contain erroneous information on cancer and can pose serious problems. There are also many good sites, which provide quality information on cancer for medical professionals, researchers and patients. This article focuses on how the Internet will aid us in fight against cancer.

Do TNFA -308 G/A and IL6 -174 G/C gene polymorphisms modulate risk of gallbladder cancer in the north Indian population?

OBJECTIVES

Gallbladder carcinoma (GBC) is highly aggressive neoplasm which arises in the background of gall stones and inflammation. GBC affects women 2-3 times more frequently than men. Pro-inflammatory TNFA and IL6 gene polymorphism has been associated with various inflammatory diseases. The aim of this study was to investigate whether TNFA -308 (G/A) and IL6 -174 G/C polymorphisms within flanking region of the genes are associated with GBC susceptibility.

METHODS

The promoter polymorphisms were genotyped using PCR-RFLP in 200 healthy subjects and 124 GBC patients.

RESULTS

Frequency distribution of TNFA -308 (G/A) and IL6 -174 G/C were not significantly different in GBC patients in comparison to healthy controls. However, frequency of TNFA -308 (G/A) polymorphism in female GBC patients without gallstone were significantly different (p-value= 0.006) when compared to healthy female subjects (OR=3.054; 95% CI=1.39-6.72).

CONCLUSION

These results suggest that TNFA -308 (G/A) polymorphism may influence the susceptibility of female gender gallbladder cancer in absence of gallstones while IL6 -174 G/C polymorphism does not seem to be playing significant role in the susceptibility to gallbladder cancer.

Frequencies of VKORC1 -1639 G>A, CYP2C9*2 and CYP2C9*3 genetic variants in the Northern Indian population

Dose requirements for oral anticoagulants in thromboembolic events are influenced by polymorphisms in VKORC1 and CYP2C9 genes. The Indian population comprises multiple ethnic groups but no data is available on allele frequencies of these genes for North Indians. The present study aimed at establishing the allele and genotype frequencies of VKORC1 -1639 G>A, CYP2C9*2 and CYP2C9*3 alleles in the North Indian population. One hundred and two healthy subjects from the Northern Indian region were genotyped for VKORC1 -1639 G>A, CYP2C9*2 and CYP2C9*3 by polymerase chain reaction and restriction fragment length polymorphism. Allele frequencies were compared with that of the HapMap populations. The allele frequencies for VKORC1 -1639 A, CYP2C9*2 and CYP2C9*3 were found to be 14.22%, 4.90% and 3.92% respectively. This report also describes the inter-ethnic differences in the Northern Indian frequencies of VKORC1 -1639 G>A, CYP2C9*2 and CYP2C9*3 alleles with that of other populations and HapMap project data. VKORC1 -1639 G>A allele is present at moderately high frequency in the Northern Indian population. The frequencies of CYP2C9*2 and CYP2C9*3 alleles are also found to be different from other populations.

Cytokine gene polymorphisms and the pathology of chronic gastritis

INTRODUCTION

Helicobacter pylori (H. pylori) infection is associated with divergent clinical outcomes and these outcomes are largely influenced by the levels of cytokines in the gastric mucosa. The levels of these cytokines are dependant on cytokine gene polymorphisms. Pro-inflammatory cytokine polymorphisms are strongly associated with severe histological changes in the gastric mucosa in Caucasian populations.

METHODS

In this study, we evaluated the role of cytokine gene polymorphisms in influencing the pathological severity of gastritis. 120 patients were evaluated. Cytokine gene polymorphisms of interleukin-1 (IL-1) beta, tumour necrosis factor alpha and the IL-1 receptor antagonist genes were done using polymerase chain reaction (PCR) restriction fragment length polymorphism and PCR variable number of tandem repeats markers typed on the deoxyribonucleic acid obtained from the peripheral blood. Histological analysis was done by using the revised Sydney system.

RESULTS

There was no association between pro-inflammatory cytokine gene polymorphisms and severity of gastritis.

CONCLUSION

This data suggests that high cytokine levels are not seen in the gastric mucosa in Indians in spite of H. pylori colonisation. IL-1 beta is a potent proinflammatory cytokine which causes a partial clearance of the organism as well as hypochlorhydria. Corporal hypochlorhydria causes a persistent colonisation by H. pylori followed by the development of gastric atrophy and later carcinoma. This lack of association with a pro-inflammatory polymorphism suggests that only low levels of IL-1 beta are present in the gastric mucosa. This causes a low clearance of the organism and a high incidence of duodenal ulceration because of hyperchlorhydria. However, it is protective against the development of gastric carcinoma. This would explain the "Indian Paradox" of the apparent discrepancy of a high degree of colonisation by H. pylori and a low incidence of gastric carcinoma in the Indian population.

Possible role of CYP2C9 & CYP2C19 single nucleotide polymorphisms in drug refractory epilepsy

BACKGROUND & OBJECTIVES

Multiple drug resistance in epilepsy is a common problem and one third of epilepsy patients remain non responsive to antiepileptic drug (AED) therapy. In this study we aimed to investigate the relationship between the genetic polymorphism of cytochrome P450 genes, namely CYP2C9 and CYP2C19 with multiple drug resistance in epilepsy patients.

METHODS

A total of 402 patients with epilepsy were enrolled in this study; 128 were drug resistant and 274 were drug responsive. The peripheral blood samples of the patients with epilepsy were collected. Drug compliance was confirmed in 20 per cent patient population using HPLC. Genotyping of CYP2C9 (FNx012 and FNx013), and CYP2C19 (FNx012 andFNx013) was carried out by PCR-RFLP.

RESULTS

The genotype frequencies of CYP2C9 430 C>T (FNx012 variant) and CYP2C9 1075 A>C (FNx013 variant) did not differ significantly in drug resistant versus responsive patients. After combining CYP2C9 FNx012 and CYP2C9 FNx013, the frequency of CYP2C9FNx011/FNx013 was significantly lower in drug resistant as compared to drug responsive epilepsy patients (P=0.03, OR=0.53, 95%CI=0.30-0.95). Similarly, combined frequency of all the slow and poor metabolizer variants (2C9 FNx011/FNx012, FNx011/FNx013 and FNx012/FNx013) was also lower as compared to drug resistant group (P=0.03, OR=0.60, 95% CI 0.38-0.96). There was no significant differences in genotypic or allelic distribution of CYP2C190FNx012 while CYP2C19FNx013 was monomorphic in northern Indian population.

INTERPRETATION & CONCLUSIONS

Our results demonstrated significant involvement of CYP2C9 genetic variants in the modulation of epilepsy pharmacotherapy confirming the important role of CYP2C9 mutants preventing epilepsy patients from developing drug resistance.

Effect on emergence from anesthesia following induction with diazepam and its association with CYP2C9, CYP2C19 and CYP3A4 gene polymorphisms

Introduction & Objectives: Benzodiazepines are commonly used as adjuvants to IV anesthetic agents. Diazepam dosage varies widely depending on the desired endpoints. The rationale behind such inter-individual variability in drug responses has been attributed to genetically determined alterations in the enzyme activities. We assessed the emergence time in patients after induction of anesthesia with two different doses of diazepam and evaluated if any correlation exists between the emergence time and genetic polymorphism in drug metabolizers CYP2C19, CYP2C9, and CYP3A4 genes. Methodology: The study was conducted on randomly selected adult patients scheduled for elective surgery between 40-60 y of age with predefined inclusion and exclusion criteria. The patients were distributed into 2 groups, with group 1 receiving 0.2 mg/kg and group 2 given 0.3 mg/kg diazepam. Wake-up time after surgery was determined after a standardized verbal command played by a tape-recorder. Three ml blood in Ethylenediaminetetraacetic acid (EDTA) was collected before administering anesthesia. Results: Wake-up time between 8-18 min did not vary between the two groups. Comparatively persons having 2C19 2 took longer time to wake-up but this association was not statistically significant. However, CYP2C9 2 and 2 C9 3 and CYP3A4 genotypes had no influence on wake-up time. Conclusion: The pilot study suggests the emergence time from diazepam is longer in patients having 2C19 2 which confers slow-metabolizer phenotype. However, this study needs to be replicated in larger sample size to arrive at definitive conclusions before clinical applications. Abbreviations: BDZ- benzodiazepine; EDTA- Ethylenediaminetetraacetic acid; GA-General Anesthesia Key words: Diazepam; Emergence; Gene Polymorphism; Pharmacogenetics Citation: Mittal T, Badhe VK, Badhe DSD, Ahluwalia P, Mitta Bl, Mittal R. Effect on emergence from anesthesia following induction with diazepam and its association with CYP2C9, CYP2C19 and CYP3A4 gene polymorphisms.  Anaesth. pain intensive care 2024;28(1):126-138. DOI: 10.35975/apic.v28i1.2380 Received: July 20, 2023; Reviewed: December 07, 2023; Accepted: December 07, 2023

Carrier analysis and prenatal diagnosis of haemophilia A in North India

The feasibility of DNA diagnosis for haemophilia A in North India was evaluated using intragenic polymorphic DNA markers in factor VIII gene for linkage analysis as well as direct detection of inversion mutation in intron 22 of the gene. The informativity of RFLP (HindIII, BclI and XbaI) and STR (introns 13 and 22) markers for linkage analysis in factor VIII gene was determined in 100 normal individuals. The observed heterozygosity for RFLP markers HindIII, BclI and XbaI was 0.63, 0.60 and 0.48 while that of STR markers introns 13 and 22 were 0.60 and 0.40 respectively. Six and four alleles were identified for introns 13 and 22 and the most frequent allele was 13(CA)26 and 22(AG)n(GT)26 with an allele frequency of 0.53 and 0.62 respectively. The heterozygosities observed for RFLP markers was higher (>70%) than the STR markers (50%) in the affected families with haemophilia A. Inversion mutation was detected in 37% of severely affected patients. Based on present and previous studies from India, a strategy has been proposed to provide molecular diagnosis to a large number of undiagnosed cases of haemophilia A.

Role of the metalloproteinase-7 (181A>G) polymorphism in gastric cancer susceptibility: a case control study in Kashmir valley

Matrix metalloproteinase-7 (MMP-7) is a small secreted proteolytic enzyme with broad substrate specificity against extracellular matrix (ECM) and non-ECM components. A promoter polymorphism MMP-7 181A>G is known to modify the gene transcription activity of the proteinase gene and influence susceptibility to various cancers. The present case-control study comprising 108 gastric cancer (GC) patients and 195 healthy controls was carried out to determine any association of this polymorphism in the Kashmir valley where the GC incidence is very high. Genotypic data were statistically analyzed by logistic regression models. In combined analysis, homozygous variant GG genotype of MMP-7 (-181A>G) polymorphism was associated with a more than two fold increased risk of GC (OR=2.13; 95% CI =1.13-4.01; p=0.020; P-trend=0.01) compared with the common AA genotype and the data fitted a recessive model. After sub-grouping based on tumor histology, the risk was more pronounced with squamous cell histology (OR=9.34; 95% CI =1.97-44.33; p=0.005) as compared to adenocarcinoma. The cancer risk due to smoking or high intake of salted tea was not influenced by the MMP-7 polymorphism. In conclusion, results from present study suggest that a common MMP-7 (181A>G) genetic polymorphism may contribute to squamous cell gastric cancer susceptibility in the Kashmir valley.

Lack of influence of DNA repair gene OGG1 codon 326 polymorphisms of gastric cancer risk in the Kashmir valley

Damage to DNA may lead to carcinogenesis but is repaired through activation of pathways involving polymorphic enzymes, including human 8-oxoguanine glycosylase 1 (OGG1). The present study aimed to assess the role of genetic variants of DNA repair gene OGG1 Ser326Cys in susceptibility to gastric cancer in Kashmir valley. A case control study was performed in 303 subjects (108 gastric cancer and 195 healthy controls), all genotyped through the polymerase chain reaction (PCR). Data were statistically analyzed using the chi-square test and the logistic regression model. The distribution of OGG1 genotypes among controls and gastric cancer cases did not show any significant differences. Although smokers and high salted tea drinkers themselves were at higher risk for gastric cancer (OR=8.975, P=0.0001; OR=14.778, P=0.0001), interaction with OGG1 Ser326Cys did not further modulate the risk. In conclusion, our findings suggest that the OGG1 polymorphism does not influence either gastric cancer risk independently or by interaction with smoking or salted-tea consumption in the Kashmir valley.

Smoking intensity, oxidative stress and chemotherapy in nonsmall cell lung cancer: a correlated prognostic study

Cigarette smoking is a well known environmental risk factor for lung cancer; furthermore it can also enhance lung carcinogenesis by free radical mediated reactions. In addition smoking affects the rates of metabolism of several drugs and may contribute to poor cancer survival. The purpose of the present work, therefore, was to see the relationship of different smoking intensities with oxidative stress and survival after platinum based chemotherapy in non-small cell lung cancer (NSCLC). The oxidative stress levels (LPO, NO, SOD, and GSH) of 144 control subjects and 203 advanced stage NSCLC patients were assessed at day '0', after the 3rd and 6th cycle of chemotherapy. Pack year (PY) was stratified in groups (1-20, 21-50, > 50) for further analysis. Groups were compared using repeated measured ANOVA, while survival curves were compared by Kaplan-Meier methods. Oxidative stress levels of smokers were significantly high (p < 0.01 or p < 0.05) as compared to non-smoker at pretreatment, after the 3rd cycle and 6th cycle of chemotherapy but not well correlated with the PY exposures. Overall mean survival of smoker patients were significantly low when compared to non-smokers. The survival of > 50 PY group was significantly lowered (p < 0.01) as compared to others PY groups, indicating that survival after chemotherapy in smoker NSCLC patients may be dependent on their PY exposures. In conclusion, smoking is a bad prognostic factor in lung cancer therapy, besides its role in oxidative stress, and poor survival. Therefore, this factor can be used in patient selection for chemoprevention.

Comparison of incorporation of wild type and mutated actins into sarcomeres in skeletal muscle cells: A fluorescence recovery after photobleaching study

The α-actin mutation G15R in the nucleotide-binding pocket of skeletal muscle, causes severe actin myopathy in human skeletal muscles. Expressed in cultured embryonic quail skeletal myotubes, YFP-G15R-α-actin incorporates in sarcomeres in a pattern indistinguishable from wildtype YFP-α-actin. However, patches of YFP-G15R-α-actin form, resembling those in patients. Analyses with FRAP of incorporation of YFP-G15R-α-actin showed major differences between fast-exchanging plus ends of overlapping actin filaments in Z-bands, versus slow exchanging ends of overlapping thin filaments in the middle of sarcomeres. Wildtype skeletal muscle YFP-α-actin shows a faster rate of incorporation at plus ends of F-actin than at their minus ends. Incorporation of YFP-G15R-α-actin molecules is reduced at plus ends, increased at minus ends. The same relationship of wildtype YFP-α-actin incorporation is seen in myofibrils treated with cytochalasin-D: decreased dynamics at plus ends, increased dynamics at minus ends, and F-actin aggregates. Speculation: imbalance of normal polarized assembly of F-actin creates excess monomers that form F-actin aggregates. Two other severe skeletal muscle YFP-α-actin mutations (H40Y and V163L) not in the nucleotide pocket do not affect actin dynamics, and lack F-actin aggregates. These results indicate that normal α-actin plus and minus end dynamics are needed to maintain actin filament stability, and avoid F-actin patches.

Genotype-phenotype correlation in Duchenne/Becker muscular dystrophy patients seen at Lucknow

The molecular basis of two allelic forms of muscular dystrophy, Duchenne (DMD) and Becker (BMD), has been explained by frame shift hypothesis. In order to test this hypothesis, deletional mutations in 59 patients confirmed to have DMD and 11 BMD patients were analysed using multiplex polymerase chain reaction and Southern hybridization with dystrophin cDNA probes. Translational reading frame of the dystrophin gene was derived from 'Border type' analysis of exons flanking the intragenic deletions. The correlation between genotype (reading frame) and phenotype (clinical severity) showed higher number of DMD patients (approximately 20%) deviating from the frame shift hypothesis. The patients who deviated had deletions at the central hot spot region of the dystrophin gene. The presence of these deviations in a large number of DMD patients highlights the difficulties in predicting the clinical progression of the disease based only on DNA profile.

Mutation analysis in spinal muscular atrophy using allele-specific polymerase chain reaction

Polymerase chain reaction (PCR), followed by restriction digestion is universally used for molecular diagnosis of spinal muscular atrophy (SMA). In the present study, we have used a modified strategy based on amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) to develop a rapid and reliable method for mutation detection and prenatal diagnosis in SMA patients. The telomeric (SMN1) and centromeric (SMN2) copies of exon 7 of the survival motor neuron (SMN) gene were amplified by ARMS-PCR, using primers specific to SMN1 and SMN2 nucleotide sequence with the exonic mismatch G (for SMN1) and A (for SMN2) at the 3' end. The PCR products were analyzed on agarose gels. All the patients who had homozygous deletion of exon 7 of SMN1 gene by conventional PCR-restriction fragment length polymorphism (PCR-RFLP) method showed the same deletion status by ARMS-PCR. This procedure showed a 100% concordance between PCR-RFLP and ARMS-PCR methods for the detection of SMN1/SMN2 status in patients with SMA. An artifact due to incomplete digestion is not a problem while using ARMS-PCR. The modified protocol is specific, rapid and highly reliable for use in prenatal diagnosis as well.