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Acta Diabetologica Dec 2015A variable number of tandem repeat (VNTRs) region in the insulin gene (INS) possibly influences the progression of type 1 diabetes (T1D) and latent autoimmune diabetes... (Meta-Analysis)
Meta-Analysis Review
AIMS
A variable number of tandem repeat (VNTRs) region in the insulin gene (INS) possibly influences the progression of type 1 diabetes (T1D) and latent autoimmune diabetes in adults (LADA). However, effects of INS VNTR polymorphisms in these contexts remain inconclusive.
METHODS
We performed a systematic review of work on the INS VNTR -2221MspI and -23HphI polymorphisms to estimate the overall effects thereof on disease susceptibility; we included 17,498 T1D patients and 24,437 controls, and 1960 LADA patients and 5583 controls.
RESULTS
For T1D, the C allele at -2221MspI and the A allele at -23HphI were associated with estimated relative risks of 2.13 (95 % CI 1.94, 2.35) and 0.46 (95 % CI 0.44, 0.48), which contributed to absolute increases of 46.76 and 46.98 % in the risk of all T1D, respectively. The estimated lambda values were 0.44 and 0.42, respectively, suggesting that a co-dominant model most likely explained the effects of -2221MspI and -23HphI on T1D. For -23HphI, the A allele carried an estimated relative risk of 0.55 (95 % CI 0.50, 0.61) for LADA and increased the risk of all LADA by 36.94 %. The λ value was 0.43, suggesting that a co-dominant model most likely explained the effect of -23HphI on LADA.
CONCLUSIONS
Our results support the existence of associations of INS with T1D and LADA.
Topics: Adult; Autoimmune Diseases; Diabetes Mellitus, Type 1; Gene Frequency; Genetic Predisposition to Disease; Humans; Minisatellite Repeats; Polymorphism, Genetic
PubMed: 26362169
DOI: 10.1007/s00592-015-0805-1 -
Lung Dec 2015Several recent studies have provided evidence that polymorphisms in the interleukin-1 (IL1) gene are implicated in tuberculosis (TB). However, results of different... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Several recent studies have provided evidence that polymorphisms in the interleukin-1 (IL1) gene are implicated in tuberculosis (TB). However, results of different studies are inconsistent. The aim of this study was to perform a meta-analysis investigating the association of the IL1B (-511 and +3954) and IL1RN VNTR polymorphisms with TB risk.
METHODS
A systematic review of the English literature was conducted by searching Pubmed, Scopus, and ISI Web of Knowledge databases for relevant studies. Pooled odds ratios (OR) with 95 % confidence intervals (CI) were calculated using fixed effects models. Between-study heterogeneity and publication bias were also evaluated.
RESULTS
Nine case-control studies including 3327 participants were reviewed and analyzed. Our results did not indicate any association of the IL1B (-511 and +3954) and IL1RN VNTR polymorphisms with TB risk in the overall populations. The pooled OR of the IL1B -511 polymorphism was 1.09 (95 % CI 0.87-1.36) for the dominant model, 1.11 (0.89-1.38) for the recessive model, 1.15 (0.87-1.50) for the homozygote model, and 1.07 (0.94-1.23) for the allelic comparison model. ORs for the IL1B +3954 and IL1RN VNTR polymorphisms were similar. In subgroup analysis stratified by ethnicity, the results revealed no association between these polymorphisms and TB risk in black people, Asians, and Caucasians, respectively. We did not identify significant between-study heterogeneity across all studies, and there was no evidence of publication bias.
CONCLUSIONS
Our results indicate there is a lack of association between the IL1B (-511 and +3954), IL1RN VNTR polymorphisms and TB risk.
Topics: Alleles; Genetic Predisposition to Disease; Genotype; Homozygote; Humans; Interleukin 1 Receptor Antagonist Protein; Interleukin-1beta; Minisatellite Repeats; Odds Ratio; Polymorphism, Genetic; Tuberculosis
PubMed: 26330006
DOI: 10.1007/s00408-015-9796-5 -
BMJ Open Jan 2015To systematically review the evidence for the impact of study design and setting on the interpretation of tuberculosis (TB) transmission using clustering derived from... (Review)
Review
Effect of study design and setting on tuberculosis clustering estimates using Mycobacterial Interspersed Repetitive Units-Variable Number Tandem Repeats (MIRU-VNTR): a systematic review.
OBJECTIVES
To systematically review the evidence for the impact of study design and setting on the interpretation of tuberculosis (TB) transmission using clustering derived from Mycobacterial Interspersed Repetitive Units-Variable Number Tandem Repeats (MIRU-VNTR) strain typing.
DATA SOURCES
MEDLINE, EMBASE, CINHAL, Web of Science and Scopus were searched for articles published before 21st October 2014.
REVIEW METHODS
Studies in humans that reported the proportion of clustering of TB isolates by MIRU-VNTR were included in the analysis. Univariable meta-regression analyses were conducted to assess the influence of study design and setting on the proportion of clustering.
RESULTS
The search identified 27 eligible articles reporting clustering between 0% and 63%. The number of MIRU-VNTR loci typed, requiring consent to type patient isolates (as a proxy for sampling fraction), the TB incidence and the maximum cluster size explained 14%, 14%, 27% and 48% of between-study variation, respectively, and had a significant association with the proportion of clustering.
CONCLUSIONS
Although MIRU-VNTR typing is being adopted worldwide there is a paucity of data on how study design and setting may influence estimates of clustering. We have highlighted study design variables for consideration in the design and interpretation of future studies.
Topics: Bacterial Typing Techniques; Cluster Analysis; Humans; Interspersed Repetitive Sequences; Minisatellite Repeats; Molecular Epidemiology; Mycobacterium tuberculosis; Polymorphism, Restriction Fragment Length; Reproducibility of Results; Research Design; Tuberculosis
PubMed: 25609667
DOI: 10.1136/bmjopen-2014-005636 -
Molecular Biology Reports Sep 2014An appropriate ratio of interleukin 1 beta to interleukin 1 receptor antagonist (IL1Ra) is required for successful pregnancy. Our objective was to study the genetic... (Meta-Analysis)
Meta-Analysis
An appropriate ratio of interleukin 1 beta to interleukin 1 receptor antagonist (IL1Ra) is required for successful pregnancy. Our objective was to study the genetic association between IL1RN variable numbers of tandem repeat (VNTR) polymorphism and recurrent pregnancy loss (RPL). To analyze the association between IL1RN VNTR allele and RPL, we investigated the IL1RN VNTR polymorphism in 136 RPL patients and in 200 healthy control women. Meta-analysis on this polymorphism was conducted to support our findings. PCR based approach was used to analyze IL1RN VNTR polymorphism and it was further confirmed by sequencing. Systematic review and meta-analysis was done using electronic database (Pub-Med, Google Scholar and Ovid) up to February 27, 2013. This meta-analysis was assessed by comprehensive meta-analysis software version 2. For meta-analysis 549 cases and 1,450 controls were included. The frequency of IL1RN genotype 2/2 was significantly higher in RPL compared to control group (AORs 3.10, 95 % CI 1.58-6.11, p = 0.001). The presence of rare allele also increased the risk of RPL significantly (ORs 1.63, 95 % CI 1.16-2.29, p = 0.004). The meta-analysis stratified by ethnicity showed that individuals with allele 2 had increased risk of RPL (OR 1.29, 95 % CI 1.04-1.61, p = 0.01), in Asians population by using fixed model. However the data of the present study clearly suggests that IL1RN VNTR polymorphism is a genetic risk factor for pregnancy loss in the study population.
Topics: Abortion, Spontaneous; Adult; Alleles; Case-Control Studies; Female; Genetic Predisposition to Disease; Genotype; Humans; India; Interleukin 1 Receptor Antagonist Protein; Interleukin-1beta; Minisatellite Repeats; Polymorphism, Genetic; Pregnancy; Risk Factors; White People; Young Adult
PubMed: 24952603
DOI: 10.1007/s11033-014-3443-8