1,721,148 research outputs found
Genetic contribution of chemokine receptor 2 (CCR2) polymorphisms towards increased serum total IgE levels in Indian asthmatics
No full textAbstractThe chemokine (C–C motif) receptors (CCR) 2 and 5 are members of a large family of G protein-coupled receptors, playing important roles in asthma pathogenesis. Using standard sequencing techniques, a total of 15 single nucleotide and 8 insertion/deletion polymorphisms (DIPs) (5 novels) were identified in and around these two genes. None of the studied polymorphisms (N=7, selected on the basis on linkage disequilibrium) was associated with asthma in a case (N=315) – control (N=337) study and showed no evidence for non-random transmission to individuals with asthma/atopy in Indian pedigrees (n=235). However, multilocus haplotype analysis based on simulations yielded a P=0.00005 in the case–control study and a P=0.03 for the family-based association studies. Furthermore, rs3918356 and rs743660 polymorphisms in CCR2 were found to be associated with total serum IgE levels in both the study designs. Thus, our study supports a significant role for chemokine receptor polymorphisms in genetic susceptibility to asthma
Four generations of sequencing: Is it ready for the clinic yet?
No full textNext-generation sequencing techniques have revolutionized over the last decade providing researchers with low cost, high-throughput alternatives compared to the traditional Sanger sequencing methods. These sequencing techniques have rapidly evolved from first-generation to fourth-generation with very broad applications such as unravelling the complexity of the genome, in terms of genetic variations, and having a high impact on the biological field. In this review, we discuss the transition of sequencing from the second-generation to the third- and fourth-generations, and describe some of their novel biological applications. With the advancement in technology, the earlier challenges of minimal size of the instrument, flexibility of throughput, ease of data analysis and short run times are being addressed. However, the need for prospective analysis and effectiveness to test whether the knowledge of any given new variants identified has an effect on clinical outcome may need improvement
Single nucleotide polymorphisms in clinics: Fantasy or reality for cancer?
No full textSingle nucleotide polymorphisms (SNPs) have been classically used for dissecting various human complex disorders using candidate gene studies. During the last decade, large scale SNP analysis i.e. genome-wide association studies (GWAS) have provided an agnostic approach to identify possible genetic loci associated with heterogeneous disease such as cancer susceptibility, prognosis of survival or drug response. Further, the advent of new technologies, including microarray based genotyping as well as high throughput next generation sequencing has opened new avenues for SNPs to be used in clinical practice. It is speculated that the utility of SNPs to understand the mechanisms, biology of variable drug response and ultimately treatment individualization based on the individual’s genome composition will be indispensable in the near future. In the current review, we discuss the advantages and disadvantages of the clinical utility of genetic variants in disease risk-prediction, prognosis, clinical outcome and pharmacogenomics. The lessons and challenges for the utility of SNP based biomarkers are also discussed, including the need for additional functional validation studies
Inducible nitric oxide synthase (iNOS): Role in asthma pathogenesis
No full textAsthma is one of the most common chronic inflammatory disorder of the airways of the lungs, affecting more than 300 million people all over the world. Nitric oxide (NO) is endogenously produced in mammalian airways by nitric oxide synthase (NOS) and is known to regulate many aspects of human asthma, including the modulation of airway and vascular smooth muscle tone and the inflammation. Asthmatic patients show an increased expression of inducible nitric oxide synthase (iNOS) in airway epithelial cells and an increased level of NO in exhaled air. Using various NO inhibitors (non-specific or iNOS-specific) and gene knock-out experiments, controversial results have been obtained regarding iNOS's beneficial and deleterious effects in the disease. In the present review, we have attempted to summarize the results of these experiments and also the genetic studies being undertaken to understand the role of iNOS in asthma. It is argued that extensive biochemical, clinical and genetic studies will be required to assess the precise role of NO in the asthma. This may help in designing selective and more potent iNOS inhibitors and NO donors for developing novel therapeutics for the asthma patients
Association of a chromosome 1q21 locus in close proximity to a late cornified envelope-like proline-rich 1 (LELP1) gene with total serum IgE levels
No full textGoing Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
A common exonic variant of interleukin21 confers susceptibility to atopic asthma
No full textBackground: Interleukin (IL)-21, an IL-2 family multifunctional cytokine, is produced by activated CD4+ T cells and is known to potentially affect growth, survival and function of numerous immune cells. As IL-21 regulates IgE production, a key mediator of various allergic disorders and asthma, it is a prime candidate gene for studying atopic asthma. Methods: In atopic asthma, analyses of four single nucleotide polymorphisms (SNP; C1455T, G1472T, C5250T and C8381T), a tetranucleotide microsatellite repeat (GAAT)n and their haplotypes were performed, and serum total IgE (TsIgE) was determined in ethnically matched unrelated patients (n = 255), unrelated controls (n = 245) and nuclear families (n = 140). Correlation between an exonic SNP C5250T in the asthmatics with serum IL-21 levels was also made. Results: In both the case-control and family study groups, the exon-3 polymorphism C5250T of the IL21 gene was significantly associated with atopic asthma and TsIgE. The C5250T polymorphism was found to affect the concentration of serum IL-21 levels in atopic asthmatics. Also, this observation was supported by the structural alteration in IL21 mRNA as predicted by mfold software. Further, our haplotypic studies indicated that while minor haplotypes 4_C_T_C_C and two locus haplotype T_C were associated with asthma in the case-control cohort, none of the major haplotypes was found to be associated with either asthma or TsIgE levels. Conclusion: Our study provides evidence that IL21 is associated with atopic asthma, TsIgE and serum IL-21 levels. Thus, it may initiate further research to elucidate the role of the IL21 gene in asthma pathogenesis
Arylamine N-acetyltransferase gene polymorphisms: markers for atopic asthma, serum IgE and blood eosinophil counts
No full textIntroduction: Polymorphisms in N-acetyltransferase 2 (NAT2), present on chromosome 8p22, are responsible for the N-acetylation variants, which segregate human populations into rapid, intermediate and slow acetylators and influence the susceptibility towards atopic disorders. We have undertaken a study of the North Indian population to screen for various NAT2 polymorphisms and to investigate their association with atopic asthma and related phenotypes. Methods: First, to establish linkage of the 8p22 region with asthma, 158 families were recruited from North India. Next, a total of 219 unrelated atopic asthmatics and 210 unrelated healthy controls were recruited for case-control disease association studies. Results: A suggestive linkage was observed with microsatellite marker D8S549, 2.6 MB upstream of NAT2. By sequencing the DNA of 40 individuals, the T111C, G191A, A434C and C759T single nucleotide polymorphisms (SNPs) in NAT2 were found to be nonpolymorphic in our population and a pattern of strong linkage disequilibrium was observed among the T341C, C481T and A803G polymorphisms. Thus, a total of 429 individuals were genotyped for the C481T and unlinked C282T polymorphisms. The C481T polymorphism was found to be significantly associated with asthma in our case-control studies at the genotype level (Armitage p = 0.00027). C481T also showed a marginal association with serum total IgE (TsIgE) (p = 0.022). Furthermore, percent blood eosinophil counts were found to be significantly higher in patients carrying the 481T allele (p = 0.0037). Significant association was also detected with respect to the C282T polymorphism and TsIgE (p = 0.008). Moreover, C_T was found to be an important risk (p = 0.001), while C_C was a major protective haplotype (p = 0.0005). The associations remained significant after Bonferroni correction for multiple testing. Conclusion: In summary, the genetic variants of the NAT2 gene do not seem to affect asthma alone, but act as modulators of asthma-related traits, such as serum IgE and blood eosinophil counts, and therefore could serve as genetic markers
Kallikrein-related peptidase 15 (prostinogen)
No full textThe third edition of the Handbook of Proteolytic Enzymes aims to be a comprehensive reference work for the enzymes that cleave proteins and peptides, and contains over 800 chapters. Each chapter is organized into sections describing the name and history, activity and specificity, structural chemistry, preparation, biological aspects, and distinguishing features for a specific peptidase. The subject of Chapter 619 is Kallikrein-related Peptidase 15 (Prostinogen)
- …
