Evaluation of the association between the common E469K polymorphism in the ICAM-1 gene and diabetic nephropathy among type 1 diabetic patients in GoKinD population

Association of ICAM-1 gene variant rs5498 (1462A>G) with non-obstructive azoospermia

The blood testicular barrier (BTB) is a barrier protecting the testes from damage. It also plays an important role in spermatogenesis. The intracellular adhesion molecule-1 (ICAM-1) is a member of the immunoglobulin cell adhesion molecule family and is a constituent component of the BTB. This study was carried out to investigate the association between the single nucleotide polymorphism (SNP) rs5498 in the ICAM-1 gene and non-obstructive azoospermia. A total of 100 male patients with non-obstructive azoospermia and 100 fertile males (healthy control) were included in this study. Genotyping of ICAM-1 gene rs5498 was performed using polymerase chain reaction-restriction enzyme fragment length polymorphism (PCR-RFLP). Both AG and GG genotypes were significantly more prevalent among the infertile men compared to the control group (p < 0.001). The odds ratio (OR) for the polymorphic allele (G) was 2.4 with 95% confidence interval from 1.38 to 3.19 (p < 0.001). The study shows that ICAM-1 rs5498 (1462A>G) SNP is positively associated with an increased risk for obstructive azoospermia, with the genotype AG heterozygotes showing a significantly higher frequency among infertile men.

Association between E469K polymorphism in the ICAM1 gene and the risk of diabetic nephropathy: a meta-analysis

BACKGROUND

Inflammation may be a key pathophysiological mechanism in diabetic nephropathy (DN). Intercellular adhesion molecule 1 (ICAM1) is an acute phase marker of inflammation. ICAM1 rs5498 has been reported to be associated with the risk of DN. However, the previous findings were conflicting due to the limited sample sizes, different methodologies and ethnicities. Therefore, this study aimed to investigate the genetic association between ICAM1 rs5498 and the risk of DN.

METHODS

Two investigators independently searched the studies from the databases PubMed, Web of Science, the Cochrane Library, Chinese National Knowledge Infrastructure (CNKI) and Embase. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the associations.

RESULTS

No significant association was detected between ICAM1 rs5498 and DN susceptibility in allelic and recessive models (p > 0.05). However, significant reduction of frequencies of the dominant model of ICAM1 rs5498 was only detected in the Caucasian subgroup (OR = 0.80; 95% CI = [0.65, 0.99], p = 0.04) and type 1 diabetes mellitus subgroup (OR = 0.80; 95% CI = [0.65, 0.99], p = 0.04).

CONCLUSIONS

Thus, ICAM1 rs5498 might be a risk factor for DN in Caucasians and type 1 diabetes mellitus patients, which suggested that ICAM1 rs5498 might help in early diagnosis and prevention of this disease. Further studies were needed to clarify the biochemical function and pathological role of ICAM1 rs5498 in the risk of DN.

Polymorphisms in the intercellular adhesion molecule 1 gene and cancer risk: a meta-analysis

OBJECTIVES

The correlation between intercellular adhesion molecule 1 (ICAM-1) common polymorphisms (rs5498 A>G and rs3093030 C>T) and cancer susceptibility has been explored in various ethnic groups and different cancer types; however, these investigations have yielded contradictory results. To address the relationship more precisely, we performed this meta-analysis.

DESIGN AND METHODS

EmBase, PubMed and China National Knowledge Infrastructure (CNKI) databases were searched by two authors independently for eligible publications before April 8, 2015. Random-effects or fixed-effects model was harnessed to calculate the pooled odds ratios (ORs) and 95% confidence intervals (CIs) when appropriate.

RESULTS

The result suggested that the ICAM-1 rs5498 A>G polymorphism is not associated with cancer susceptibility in overall cancer. In a stratified analysis by ethnicity, a significant increased cancer risk was identified among Asians, but the inverse association was found among Caucasians. In a stratified analysis by cancer type, ICAM-1 rs5498 A>G polymorphism was associated with a significantly increased risk of oral cancer, but with protection from colorectal cancer and melanoma. ICAM-1 rs3093030 C>T polymorphism is not correlated with cancer susceptibility.

CONCLUSIONS

In summary, this meta-analysis highlights that the ICAM-1 rs5498 A>G polymorphism probably contributes to decreased susceptibility to cancer, especially in Caucasians, in melanoma and colorectal cancer subgroup, but it may be a risk factor for oral cancer and Asians.

Intracellular adhesion molecule-1 K469E gene polymorphism and risk of diabetic microvascular complications: a meta-analysis

BACKGROUND

A number of studies evaluated the association of intracellular adhesion molecule-1 (ICAM-1) K469E (rs5498, A/G) gene polymorphism with diabetic microvascular complications (DMI) including diabetic nephropathy (DN) and diabetic retinopathy (DR) in different populations. However, the results of individual studies remain conflicting.

METHODS

A comprehensive search was conducted to identify all eligible studies of the above-mentioned associations. The pooled odds ratios (ORs) and 95% confidence intervals (CIs) were assessed using the fixed or random effect model.

RESULTS

Seven studies involving 3411 subjects were included. Overall, the meta-analysis showed a significant association of the A allele with increased risk of DMI susceptibility in a recessive model (OR = 1.37, 95% CI 1.04-1.80, P = 0.02). In the subgroup analysis stratified by ethnicity, significant association was found in Asians but not in Caucasians (OR = 1.78, 95% CI 1.13-2.81, P = 0.01; OR = 1.10, 95% CI 0.79-1.54, P = 0.58, respectively). Moreover, it showed a significant association between the A allele and risk of DN in a recessive model (OR = 1.25, 95% CI 1.02-1.55, P = 0.04).

CONCLUSIONS

This meta-analysis suggested that the K469E polymorphism in ICAM-1 gene might affect individual susceptibility to DMI and showed a discrepancy in different ethnicities. Further investigations are needed to validate the association.

ICAM-1 K469E polymorphism is a genetic determinant for the clinical risk factors of T2D subjects with retinopathy in Indians: a population-based case-control study

OBJECTIVE

Elevated levels of intercellular adhesion molecule-1 (ICAM-1) are demonstrated in diabetes complications. The current study aims to understand association of K469E (rs5498) in ICAM-1 gene, in type 2 diabetic (T2D) subjects with retinopathy.

DESIGN

Case-control study.

SETTING

Sankara Nethralaya Diabetic Retinopathy Epidemiology and Molecular Genetic Study, an epidemiology study (on prevalence of diabetic retinopathy in T2D subjects (T2DR) from south India) and outpatient department of Sankara Nethralaya, a tertiary care hospital, in Chennai, India.

PARTICIPANTS

A total of 356 T2D subjects of >15 years of diabetes duration, with (n=199) and without (n=157) retinopathy.

METHODS

The rs5498 polymorphism was genotyped by direct sequencing. Multivariate analysis for various clinical covariates was done using SPSS V.14. Comparative assessment of structure stability, folding rate of the variants were assessed using bioinformatics tools like STRIDE, MuPro, ModellerV97, fold rate server, etc.

RESULTS

The AA genotype of rs5498 was seen at a higher frequency in the retinopathy group (p=0.012). The risk for diabetic retinopathy (DR) increased in the presence of AA genotype (OR=1.89-4.82) after the sequential addition of various clinical covariates. Multivariate logistic regression analysis showed 8.26 times high risk for developing DR in the AG genotype (p=0.003). Structural superimposition of ICAM-1 wild type (K469) and variant (E469) showed 0.943 Å of backbone root mean square deviation as calculated by PYMOL software. A difference in the fold rate time was also observed between the wild type (5.4/s) and variant (3.3/s).

CONCLUSIONS

This study shows that allele A of rs5498 in ICAM-1 is a putative risk predisposing allele for T2D retinopathy and its clinical covariates in Indian population. The folding rate of the protein decreases for the A allele implicating a potential effect on the structure and function of ICAM-1.

Association of intercellular adhesion molecule 1 (ICAM1) with diabetes and diabetic nephropathy

Diabetes and diabetic nephropathy are complex diseases affected by genetic and environmental factors. Identification of the susceptibility genes and investigation of their roles may provide useful information for better understanding of the pathogenesis and for developing novel therapeutic approaches. Intercellular adhesion molecule 1 (ICAM1) is a cell surface glycoprotein expressed on endothelial cells and leukocytes in the immune system. The ICAM1 gene is located on chromosome 19p13 within the linkage region of diabetes. In the recent years, accumulating reports have implicated that genetic polymorphisms in the ICAM1 gene are associated with diabetes and diabetic nephropathy. Serum ICAM1 levels in diabetes patients and the icam1 gene expression in kidney tissues of diabetic animals are increased compared to the controls. Therefore, ICAM1 may play a role in the development of diabetes and diabetic nephropathy. In this review, we present genomic structure, variation, and regulation of the ICAM1 gene, summarized genetic and biological studies of this gene in diabetes and diabetic nephropathy and discussed about the potential application using ICAM1 as a biomarker and target for prediction and treatment of diabetes and diabetic nephropathy.

Insights to the genetics of diabetic nephropathy through a genome-wide association study of the GoKinD collection

The Genetics of Kidneys in Diabetes (GoKinD) study was initiated to facilitate research aimed at identifying genes involved in diabetic nephropathy (DN) in type 1 diabetes. In this review, we present an overview of this study and the various reports that have used its collection. At the forefront of these efforts is the recent genome-wide association scan implemented on the GoKinD collection. We highlight the results from our analysis of these data and describe compelling evidence from animal models that further support the potential role of associated loci in the susceptibility of DN. To enhance our analysis of genetic associations in GoKinD, using genome-wide imputation, we expanded our analysis of this collection to include genotype data from more than 2.4 million common single nucleotide polymorphisms. We illustrate the added utility of this enhanced dataset through the comprehensive fine-mapping of candidate genomic regions previously linked with DN and the targeted investigation of genes involved in candidate pathways implicated in its pathogenesis. Collectively, genome-wide association and genome-wide imputation data from the GoKinD collection will serve as a springboard for future investigations into the genetic basis of DN in type 1 diabetes.

A single nucleotide polymorphism alters the sequence of SP1 binding site in the adiponectin promoter region and is associated with diabetic nephropathy among type 1 diabetic patients in the Genetics of Kidneys in Diabetes Study

OBJECTIVE

The adiponectin promoter single nucleotide polymorphism (SNP) -11391G/A is found to be associated with nephropathy in type 1 diabetic (T1D) patients among Danish, but not French, Finnish, and Swedish populations. In the present study, we identified the binding sites for transcriptional factors in the adiponectin promoter region and also evaluated the association between adiponectin promoter polymorphisms and diabetic nephropathy (DN) in T1D patients.

MATERIALS AND METHODS

Three adiponectin promoter SNPs, including -11377C/G, -11391G/A, and -11426A/G, were genotyped with dynamic allele-specific hybridization. The subjects included 1177 American T1D patients (622 females/555 males) with or without DN. All patients are of European descent and selected from the Genetics of Kidneys in Diabetes (GoKinD) study.

RESULTS

We identified four binding sites of transcriptional stimulatory protein (SP1) in the adiponectin putative promoter and found that the G allele of SNP -11377C/G altered the sequence for one of the SP1 binding sites. This polymorphism was significantly associated with DN in female T1D patients (P=.022, OR=1.352, 95% CI=1.044-1.752). Further analyses indicated the common diplotype (haplotypic genotype) H1/H1, constructed with SNPs -11377C/G and -11391G/A, was significantly associated with DN in females (P=.013), while the association of another diplotype H1/H2 with DN in females was of borderline significance (P=.071).

CONCLUSIONS

The present study thus provides the first evidence that SNP -11377C/G alters the sequence in one of the SP1 binding sites in the adiponectin promoter region. This polymorphism, together with another promoter SNP -11391G/A, may confer susceptibility to the development of DN in T1D patients among the GoKinD population.

A candidate gene approach to genetic prognostic factors of IgA nephropathy--a result of Polymorphism REsearch to DIstinguish genetic factors Contributing To progression of IgA Nephropathy (PREDICT-IgAN)

BACKGROUND

Renal prognosis of IgA nephropathy (IgAN) is affected by environmental and genetic factors. Other studies demonstrated that some atherosclerotic disease-related genes were significantly associated with renal prognosis.

METHODS

The Polymorphism REsearch to DIstinguish genetic factors Contributing To progression of IgAN (PREDICT-IgAN) was a multicentre retrospective observational study to investigate associations between progression of IgAN (a 50% increase of serum creatinine level and slope of eGFR) and a hundred atherosclerotic disease-related gene polymorphisms, mainly single nucleotide polymorphisms (SNPs) in 320 IgAN patients who had more than a normal range of urinary protein (> or =0.25 g/day) at diagnosis.

RESULTS

During 8.3 +/- 4.2 years of a follow-up period, 83 patients (25.9%) developed progression. In log-rank tests, glycoprotein Ia GPIa C807T and G873A and intercellular adhesion molecule-1 ICAM-1 A1548G (K469E) were found to be significantly associated with progression even after adjustment for multiple comparisons by the method of Bonferroni (adjusted P = 0.0174, 0.0176 and 0.0430, respectively). In a multivariate Cox proportional-hazards model, GPIa 807TT (873CC) [versus 807TT, adjusted hazard ratio 2.05 (95% confidence interval 1.13-3.71)] and ICAM-1 1548GG [versus 1548AA, 2.55 (1.40-4.65)] were identified as independent genetic predictors of progression, along with conventional clinical prognostic factors such as eGFR, urinary protein and use of antihypertensives at diagnosis.

CONCLUSIONS

PREDICT-IgAN distinguished GPIa C807T/ G873A and ICAM-1 A1548G from multiple athero- sclerotic disease-related gene polymorphisms by their predictive indicator for progression of IgAN.