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1.
Thalassemia has been recognized by the World Health Organization as important inherited disorders principally impacting on the populations of low income countries. In this report, the prevalence of common β-thalassemia mutations in India was defined in 126 β-thalassemia carrier subjects in a western Indian population mainly from the south-western Maharashtra. The six most common β-thalassemia mutations were detected, which included IVS I-5 (G–C), IVS I-1 (G–T), codon 8–9 (+G), codon 41/42 (–TCTT), Codon 15 (G–A), and 619 bp deletion at 3′ end of β-globin gene. These mutations accounted for 93.66 % in 126 β-thalassemia carrier subjects and 6.34 % remained uncharacterized. Out of 126, 82 (65.07 %) showed the most common (prevalent) type of mutation, IVS I-5 (G–C), followed by IVS I-1 (G–T) showed by 12 (9.52 %) subjects. Three (2.38 %) subjects showed 619 bp deletion, codon 8/9 (+G) and codon 15 (G–A) mutations were present in eight subjects each (6.34 %). Only five (3.96 %) subjects showed codon 41/42 (–TCTT). There were eight (6.34 %) subjects where mutation was not any of the six mutations studied. This study provides the pattern of β thalassemia mutations from south-western Maharashtra, which will help to prevent β-thalassemia using prenatal diagnosis and proper counseling.

Electronic supplementary material

The online version of this article (doi:10.1007/s12291-012-0230-y) contains supplementary material, which is available to authorized users.  相似文献   

2.
Cystic Fibrosis Trans membrane conductance regulator (CFTR) gene is an asthma susceptibility gene. In the present study we investigated the possible association of CFTR gene mutations in Indian asthmatic children as compared to controls. The study included 250 asthmatics and 250 age and sex matched controls. Case to control ratio for sample size was 1:1. Genotyping was performed for 24 CFTR gene mutations by ARMS-PCR and PCR–RFLP method. Among 24 CFTR gene mutations, heterozygous allele of R553X mutation was found in 4 (1.6 %) asthmatic cases and 2 (0.8 %) controls. Value of FVC and FEV1/FVC ratio were significantly lower in heterozygous individuals (p value <0.05). No significant difference was observed in the genotype and allele frequency of R553X mutation (OR = 1.339, 95 % CI = 0.755–2.374, p value = 0.685). Furthermore, all wild type homozygous alleles were observed in remaining 23 CFTR gene mutations. Our data concludes that R553X mutation was not significantly associated in Indian asthmatic children.  相似文献   

3.
The present study was conducted on North Indian population to observe rpoB gene mutation profile in multidrug resistant Mycobacterium tuberculosis. This was an observational study. 30 cases of MDR-TB proven by culture and drug sensitivity were selected. DNA sequencing of 81 bp (codon 507–533) long RRDR of Mycobacterium tuberculosis was done to detect the sites of mutation. Out of 30 cases, 24 showed a single mutation in the RRDR region of rpoB gene in which 16 (53.33 %) showed mutation in codon 531(TCG→TTG), 5 cases (16.66 %) showed mutation in codon 526(CAC→TAC), mutation in codon 516(GAC→GTC, AAC) was present in 3 cases (10 %). It was also observed that mutation in more than one codon was present in 4 cases (13.33 %), which included deletion at codon 509(AGC→–GC), mutation at 513(CAA→CTA), 516, 526, 529(CGA→CTA) and 531. No mutation was detected in RRDR in 2 cases (6.66 %). Our finding of 13.33 % cases with multiple sites of mutation in RRDR region is in contrast to earlier studies done in North India which showed single mutation detected in RRDR of rpoB gene that highlights the emerging change in the trend of mutation profile of rpoB gene in rifampicin resistant Mycobacterium tuberculosis.  相似文献   

4.
Nicotine, responsible for the addictive properties of tobacco, is widely used in nicotine replacement therapy for tobacco use cessation. We investigated the time-dependent effect of treatment with nicotine on the tumor suppressor, DNA repair and immune responses. Swiss Albino mice (laca strain) of both sexes received nicotine dissolved at a dose of 100 µg/ml in 2% sucrose for 24 weeks, by oral gavage, while age- and gender-matched controls received only 2% sucrose for the same period. Nicotine-treated and control mice were sacrificed 6, 16 and 24 weeks post-treatment, and their tissues evaluated for alterations in histology, oxidative stress, TNF-α levels, nitric oxide (NO) and myeloperoxidase (MPO) release, tumor suppressor response and DNA repair response. Statistical significance of results was determined using Students’ t test. The tissues of nicotine treated mice exhibited a large number of multinucleated and binucleated cells, enlarged nuclei and non-uniform distribution of cells, significant increase in expression of TNF-α gene and serum TNF-α, and time-dependent significant increase in lipid peroxidation, protein carbonylation, NO and MPO release when compared to age-and gender-matched controls. The mRNA expression of the tumor suppressor gene p53, its primary regulator Mdm2, and the DNA repair genes Brca2 and Ape1 were significantly elevated, but the corresponding protein levels remained largely unaltered. In conclusion, treatment with nicotine caused oxidative stress and inflammation which can cause widespread cellular damage from the very onset of treatment, without subverting the tumor suppressor and DNA repair responses.Electronic supplementary materialThe online version of this article (10.1007/s12291-020-00903-8) contains supplementary material, which is available to authorized users.  相似文献   

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Vitamin B12 deficiency has been reported in patients with Autoimmune thyroid disorders. However there is limited data on exact prevalence of low B12 and its correlation with anti-thyroperoxidase antibody (anti-TPO) levels in these patients. The aim of our study was to estimate serum vitamin B12 levels in autoimmune thyroid disorders and to correlate B12 levels with anti-TPO. 350 patients were selected by convenient sampling. Vitamin B12 levels and thyroid parameters were estimated using fully automated chemiluminescence method on Access 2. Results of our study shows that using the manufacturer’s cut-off of 145 pg/mL, the prevalence of low serum vitamin B12 was found to be 45.50 %. Higher prevalence (55 %) was seen based on the published cut-off of 200 pg/mL The study however did not demonstrate any significant correlation between vitamin B12 levels and anti-TPO (r = −0.11 and p value of 0.30).

Electronic supplementary material

The online version of this article (doi:10.1007/s12291-014-0418-4) contains supplementary material, which is available to authorized users.  相似文献   

8.
BackgroundMany human genetic diseases arise from point mutations. These genetic diseases can theoretically be corrected through gene therapy. However, gene therapy in clinical application is still far from mature. Nearly half of the pathogenic single-nucleotide polymorphisms (SNPs) are caused by G:C>A:T or T:A>C:G base changes and the ideal approaches to correct these mutations are base editing. These CRISPR-Cas9-mediated base editing does not leave any footprint in genome and does not require donor DNA sequences for homologous recombination. These base editing methods have been successfully applied to cultured mammalian cells with high precision and efficiency, but BE4 has not been confirmed in mice. Animal models are important for dissecting pathogenic mechanism of human genetic diseases and testing of base correction efficacy in vivo. Cytidine base editor BE4 is a newly developed version of cytidine base editing system that converts cytidine (C) to uridine (U).ResultsIn this study, BE4 system was tested in cells to inactivate GFP gene and in mice to introduce single-base substitution that would lead to a stop codon in tyrosinase gene. High percentage albino coat-colored mice were obtained from black coat-colored donor zygotes after pronuclei microinjection. Sequencing results showed that expected base changes were obtained with high precision and efficiency (56.25%). There are no off-targeting events identified in predicted potential off-target sites.ConclusionsResults confirm BE4 system can work in vivo with high precision and efficacy, and has great potentials in clinic to repair human genetic mutations.How to cite: Adlat S, Hayel F, Yang P, et al. CRISPR-mediated base editing in mice using cytosine deaminase base editor 4. Electron J Biotechnol 2021;52. https://doi.org/10.1016/j.ejbt.2021.04.010  相似文献   

9.
Hemoglobin (Hb) Grey Lynn is a Hb variant caused by a substitution of Phe for Leu at position 91 of α1-globin chain, originally described in individual of unknown ethnic background. This article addresses the interaction of Hb Grey Lynn with a non-deletional α+-thalassemia found in Thailand, a hitherto un-described condition. The proband was adult Thai woman referred for investigation of mild anemia with Hb 90 g/L. Hb analyses using low pressure liquid chromatography raised a suspicion of abnormal Hb presence, which was failed to demonstrate by cellulose acetate electrophoresis and capillary electrophoresis. DNA sequencing identified a CTT (Leu) to TTT (Phe) mutation at codon 91 corresponding to the Hb Grey Lynn (Vientiane) [α91(FG3)Leu>Phe (α1) on α1-globin gene and a C deletion between codons 36 and 37 on α2-globin gene causing α+-thalassemia. As compared to those observed in a compound heterozygote for Hb Grey Lynn / α0-thalassemia reported previously, higher MCV (81.7 fL) and MCH (26.3 pg) values with a lower level of Hb Grey Lynn (19.7%) were observed in the proband. The normochromic normocytic anemia observed could be due to the interaction of Hb Grey Lynn with α+-thalassemia. The two mutations could be identified using PCR-RFLP and allele-specific PCR assays developed.  相似文献   

10.
Hepcidin is a 25-amino acid peptide hormone produced by hepatocytes and plays a key role in body iron metabolism. Hepcidin deficiency is the cause of iron overload in hereditary hemochromatosis, iron-loading anemia, and its excess is associated with anemia of inflammation, chronic disease and iron deficiency anemia (IDA). The aims of this study was to evaluate HAMP gene mutation, namely IVS2 + 1(–G) (c.148–150 + 1del) and Gly71 Asp (c.212G > A (rs104894696) association with iron status in IDA conditions. Our study participants were 500 IDA patients and 550 age and sex-matched healthy controls. Hepcidin, ferritin and CRP analysis was done by ELISA method while ESR analysis was done according to Wintrobe method. CBC analysis was done by auto-analyzer. Two mutations in the HAMP genes were analysed by PCR RFLP method. Among the IDA patients, 7 were heterozygous for Met50del IVS2 + 1(–G) mutation. Nine IDA patients were heterozygous for G71D G–A mutation and homozygous were not identified in both mutations.Controls were showing heterozygous frequency 1.8 and 2.1% of Met50del IVS2 + 1(–G) and G71D G–A mutations respectively. Mutation of HAMP (Met50del IVS2 + 1(–G) and G71D G–A) were clinically associated with IDA and act as modulator of disease.  相似文献   

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IntroductionAn appropriate management of anaemia laboratory tests is crucial for a correct diagnosis and treatment. A non-sequential “shotgun” approach (where every anaemia related test is ordered) causes workload and cost increases and could be potentially harmful. We have implemented a Decision Support System through our laboratory information system (LIMS) based on reflexive algorithms and automatic generation of interpretative reports specifically in diagnosis of anaemia for primary care patients.Materials and methodsWhen a request contained an “Anaemia Suspicion Study” profile, more than twenty automatic reflexive rules were activated in our LIMS based upon laboratory results. These rules normally involved the addition of reflexive tests. A final report was automatically generated for each interpretation which was always reviewed for their validity by two staff pathologists. We measured the impact of this system in the ordering of most common anaemia related tests and if a proper treatment was established based on the interpretive report.ResultsFrom all the studies performed, only 12% were positive being “iron deficiency” and “anaemia of chronic disease” the most frequent causes, 62% and 17%, respectively. Proper treatment was established in 88% of these anaemic patients. Total iron, transferrin, ferritin, folate and vitamin B12 demand decreased substantially after implementation representing a cost reduction of 40% only for these five tests.ConclusionsOur system has easily improved patient outcomes, advising on individual clinical cases. We have also noticeably reduced the number of over-requested tests and laboratory costs.  相似文献   

13.

Introduction:

Additional nucleotide substitutions in the 3′-untranslated region of prothrombin gene could explain some thrombotic events and also adverse pregnancy outcomes. We describe the first case of a homozygous 20209C>T mutation as the cause of deep vein thrombosis in a Spanish patient.

Case and methods:

The 56-year-old male patient with a partial tear of the Achilles tendon developed calf (tibial) deep vein thrombosis after immobilization and was treated with an anticoagulant. To determine if the deep vein thrombosis was of genetic origin, a peripheral blood DNA sample was analysed for the presence of the three most frequent mutations associated with thrombotic events: factor V Leiden (1691G>A), prothrombin (20210G>A) and methylene tetrahydrofolate reductase (677C>T). The presence or absence of the normal allele of prothrombin could not be determined using the PTH-FV-MTHFR StripAssay (Vienna Lab).

Results:

Comprehensive analysis showed that the patient had a variant interfering with the polymerase chain reaction product, we sequenced the entire prothrombin gene and found that the patient had a homozygous C>T mutation at position 20209; this interfered with the polymerase chain reaction product, which needs a C at this position to be able to bind to the wild-type probe present in the test strip.

Conclusion:

The homozygous 20209C>T mutation and the presence of the mutation 677C>T in heterozygosity explained the patient’s deep vein thrombosis because the combination of mutations would increase the risk of thrombosis. Suitable genetic counselling should be provided to the patient and first-degree relatives as it important to detect prothrombin gene variants that could increase risk for thrombotic events.  相似文献   

14.
In the era of the targeted therapy identification of EGFR mutation detection in lung cancer is extremely helpful to predict the treatment efficacy of EGFR tyrosine kinase inhibitors (TKIs). Unfortunately, the inadequacy and quality of the biopsy samples are the major obstacles in molecular testing of EGFR mutation in lung cancer. To address this issue, the present study intended to use liquid biopsy as the non-invasive method for EGFR mutation detection. A total of 31 patients with an advanced stage of lung cancer were enrolled in the study from which cell-free DNA (cfDNA) and FFPE tissue DNA was extracted. Extracted DNA samples were analyzed for further EGFR exon specific mutation analysis by ARMS-PCR. Data were analyzed statistically using SPSS software. In cfDNA samples, the prevalence of wild type EGFR was 48% while the prevalence of TKI resistant and TKI sensitive mutations were 3%. Conversely, in tissue DNA samples, the prevalence of wild type, TKI sensitive and TKI resistant mutations were 48%, 19%, and 3%, respectively. The overall concordance of EGFR mutation between cfDNA and tissue DNA was 83%. McNemar’s test revealed that there was no significant difference between EGFR expression of cfDNA and tissue DNA samples. Additionally, the significant-high incidence of TKI resistant mutations was observed in tobacco habituates, indicating the role of carcinogens present in the tobacco in developing resistant mutations. In conclusion, our data suggest that evaluation of EGFR mutation from cfDNA samples is practicable as a non-invasive tool in patients with advanced-stage of lung cancer.  相似文献   

15.
BackgroundYacon (Smallanthus sonchifolius) is a root crop native to the Andean region. Low sexual reproductive capacity is a major constraint facing the genetic breeding of this crop. Biotechnological techniques offer alternative ways to widen genetic variability. We investigated somaclonal variation in regenerants of yacon derived from in vitro somatic embryogenesis using simple sequence repeat (ISSR) analysis and flow cytometry.ResultsTwenty tested ISSR primers provided a total of 7848 bands in 60 in vitro regenerants and control plant. The number of bands for each primer varied from 3 to 10, and an average of 6.95 bands was obtained per ISSR primer. Eight primers were polymorphic and generated 10 polymorphic bands with 7.19% mean polymorphism. ISSR analysis revealed genetic variability in 6 plants under study. These regenerants had Jaccard's distances 0.104, 0.020, 0.040, 0.106, 0.163 and 0.040. Flow cytometric analysis did not reveal changes of relative nuclear DNA content in regenerants suggesting that the plants obtained via somatic embryogenesis had maintained stable octoploid levels.ConclusionsOur findings show that indirect somatic embryogenesis could be used in yacon improvement to widen genetic variability, especially when low sexual reproductive capacity hinders classical ways of breeding.  相似文献   

16.
To detect the site of mutation in RRDR of rpo B gene for rifampicin resistance in MDR-TB by DNA sequencing. 50 MDR-TB patients were enrolled in our study after informed written consent. Mycobacterial DNA was extracted from sputum samples by Universal Sample Processing (USP) method and RRDR of rpo B gene was amplified by PCR using primers RP4T and RP8T and then sequenced by automated DNA sequencing. The nucleotide sequences of RRDR of rpo B gene were compared with the reference sequence. We observed three different types of mutation in the RRDR of rpo B gene. The frequency of mutation in codon 531 (TCG → TTG), 526 (CAC → TAC) and 516 (GAC → GTC) are 60, 26.6 and 6.6% respectively. Of the total cases studied, 6.6% cases, although resistant to rifampicin, did not show any mutation in the RRDR of rpo B gene. Codon 531 (TCG → TTG) is the most common site of mutation in RRDR of rpo B gene for rifampicin resistance in MDR-pulmonary tuberculosis followed by codon 526 (CAC → TAC) and codon 516 (GAC → GTC).  相似文献   

17.
BackgroundZymomonas mobilis is a Gram-negative microaerophilic bacterium with excellent ethanol-producing capabilities. The RecET recombination system provides an efficient tool for direct targeting of genes in the bacterial chromosome by PCR fragments.ResultsThe plasmids pSUZM2a-RecET and pSUZM2a-RecE588T were first developed to co-express RecE or RecE588 and RecT for homologous recombination. Thereafter, the PCR fragments of the tetracycline resistance marker gene flanked by 60 bp of adhA (alcohol dehydrogenase I) or adhB (alcohol dehydrogenase II) homologous sequences were electroporated directly into ZM4 cells harboring pSUZM2a-RecET or pSUZM2a-RecE588T. Both adhA and adhB were replaced by the tetracycline resistance gene in ZM4, yielding two mutant strains, Z. mobilis ZM4 ΔadhA and Z. mobilis ZM4 ΔadhB. These two mutants showed varying extent of reduction in ethanol production, biomass generation, and glucose metabolism. Furthermore, enzyme activity of alcohol dehydrogenase II in Z. mobilis ZM4 ΔadhB exhibited a significant reduction compared to that of wild-type ZM4.ConclusionThis approach provided a simple and useful method for introducing mutations and heterologous genes in the Z. mobilis genome.  相似文献   

18.
Genome-wide association studies have discovered multiple single nucleotide polymorphisms (SNPs) associated with the risk of common diseases. The objective of this study was to demonstrate the replication of previously published SNPs that showed statistical significance for breast cancer in the Malaysian population. In this case–control study, 80 subjects for each group were recruited from various hospitals in Malaysia. A total of 768 SNPs were genotyped and analyzed to distinguish risk and protective alleles. A total of three SNPs were found to be associated with increased risk of breast cancer while six SNPs showed protective effect. All nine were statistically significant SNPs (p ≤ 0.01), five SNPs from previous studies were successfully replicated in our study. Significant modifiable (diet) and non-modifiable (family history of breast cancer in first degree relative) risk factors were also observed. We identified nine SNPs from this study to be either conferring susceptibility or protection to breast cancer which may serve as potential markers in risk prediction.

Electronic supplementary material

The online version of this article (doi:10.1007/s12291-013-0414-0) contains supplementary material, which is available to authorized users.  相似文献   

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BackgroundThe enzymes utilized in the process of beer production are generally sensitive to higher temperatures. About 60% of them are deactivated in drying the malt that limits the utilization of starting material in the fermentation process. Gene transfer from thermophilic bacteria is a promising tool for producing barley grains harboring thermotolerant enzymes.ResultsGene for α-amylase from hydrothermal Thermococcus, optimally active at 75–85°C and pH between 5.0 and 5.5, was adapted in silico to barley codon usage. The corresponding sequence was put under control of the endosperm-specific promoter 1Dx5 and after synthesis and cloning transferred into barley by biolistics. In addition to model cultivar Golden Promise we transformed three Slovak barley cultivars Pribina, Levan and Nitran, and transgenic plants were obtained. Expression of the ~ 50 kDa active recombinant enzyme in grains of cvs. Pribina and Nitran resulted in retaining up to 9.39% of enzyme activity upon heating to 75°C, which is more than 4 times higher compared to non-transgenic controls. In the model cv. Golden Promise the grain α-amylase activity upon heating was above 9% either, however, the effects of the introduced enzyme were less pronounced (only 1.22 fold difference compared with non-transgenic barley).ConclusionsExpression of the synthetic gene in barley enhanced the residual α-amylase activity in grains at high temperatures.  相似文献   

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