Genetic analysis of IREB2, FAM13A and XRCC5 variants in Chinese Han patients with chronic obstructive pulmonary disease

Evaluation of rs10811661 polymorphism in CDKN2A / B in colon and gastric cancer

One of the causes of colon and gastric cancer is the dysregulation of carcinogenic genes, tumor inhibitors, and micro-RNA. The purpose of this study is to apply rs10811661 polymorphism in CDKN2A /B gene as an effective biomarker of colon cancer and early detection of gastric cancer. As a result,400 blood samples, inclusive of 200 samples from healthy individuals and 200 samples (100 samples from intestinal cancer,100 samples from stomach cancer) from the blood of someone with these cancers, to determine the genotype of genes in healthful and ill people through PCR-RFLP approach and Allelic and genotypic tests of SPSS software. To observe the connection between gastric cancer and bowel cancer risk and genotypes, the t-student test for quantitative variables and Pearson distribution for qualitative variables have been tested and the results have been evaluated using the Chi-square test. The effects confirmed that the highest frequency of TT genotypes is in affected individuals and CC genotype is in healthful individuals. In addition, it confirmed that women were more inclined than men to T3 tumor invasion and most grade II and III colon cancers, and in older sufferers with gastric cancer, the grade of tumor tended to be grade I. Among genetic variety and rs10811661, with invasiveness, there is a tumor size and degree in the affected person. In summary, our findings suggest that the rs10811661 polymorphism of the CDKN2A / B gene is strongly associated with the occurrence of intestinal cancer and stomach is linked to its potential role as a prognostic biomarker for the management of bowel cancer and stomach.

Single Nucleotide Polymorphisms of FAM13A Gene in Chronic Obstructive Pulmonary Disease-A Case Control Study in Vietnam

BACKGROUND

In 2018, GOLD addressed the issues of genotypes associated with risk factors for COPD. The genome-wide association study (GWAS) demonstrated an association between COPD and several genetic variants of single nucleotide polymorphisms (SNPs) of the FAM13A gene with the risk of COPD.

OBJECTIVE

To study the single nucleotide polymorphisms rs2869967 and rs17014601 of the FAM13A gene in chronic obstructive pulmonary disease. Subjects and research methods: 80 subjects diagnosed with COPD and 80 subjects determined not to have COPD according to GOLD 2020 criteria; the subjects were clinically examined, interviewed, and identified as possessing single nucleotide polymorphisms using the sanger sequencing method on whole blood samples.

RESULTS

The male/female ratio of the patient group and the control group was 79/1 and 39/1, respectively. The percentages of C and T alleles of rs2869967 in COPD patients were 50.6% and 49.4%, respectively. The percentages of C and T alleles of rs17014601 in COPD patients were 31.9% and 68.1%, respectively. At rs17014601, the ratio values of alleles T and C in the disease group and the control group were markedly different, making them statistically reliable (p = 0.031). The rate of CT genotype in the group of patients was considerably higher than that of the control group. The TT homozygous genotype had a lower risk of COPD compared with the other genotypes in the dominant model (ORTT/(CC + CT) = 0.441; CI95% = 0.233-0.833); this difference was statistically significant (p = 0.012).

CONCLUSIONS

With rs17014601, it is characteristic that the frequency of the T allele appears more than the C allele, and the CT heterozygous phenotype accounts for the highest proportion in rs17014601 and rs2869967 recorded in COPD patients. There is an association between the genetic variant of the SNP FAM13A-rs17014601 and the risk of COPD.

The Influence of FAM13A and PPAR-γ2 Gene Polymorphisms on the Metabolic State of Postmenopausal Women

Recently, we have observed two significant pandemics caused by communicable (COVID-19) and non-communicable factors (obesity). Obesity is related to a specific genetic background and characterized by immunogenetic features, such as low-grade systemic inflammation. The specific genetic variants include the presence of polymorphism of the Peroxisome Proliferator-Activated Receptors gene (PPAR-γ2; Pro12Ala, rs1801282, and C1431T, rs3856806 polymorphisms), β-adrenergic receptor gene (3β-AR; Trp64Arg, rs4994), and Family With Sequence Similarity 13 Member A gene (FAM13A; rs1903003, rs7671167, rs2869967). This study aimed to analyze the genetic background, body fat distribution, and hypertension risk in obese metabolically healthy postmenopausal women (n = 229, including 105 lean and 124 obese subjects). Each patient underwent anthropometric and genetic evaluations. The study has shown that the highest value of BMI was associated with visceral fat distribution. The analysis of particular genotypes has revealed no differences between lean and obese women except for FAM13A rs1903003 (CC), which was more prevalent in lean patients. The co-existence of the PPAR-γ2 C1431C variant with other FAM13A gene polymorphisms [rs1903003(TT) or rs7671167(TT), or rs2869967(CC)] was related to higher BMI values and visceral fat distribution (WHR > 0.85). The co-association of FAM13A rs1903003 (CC) and 3β-AR Trp64Arg was associated with higher values of systolic (SBP) and diastolic blood pressure (DBP). We conclude that the co-existence of FAM13A variants with C1413C polymorphism of the PPAR-γ2 gene is responsible for body fat amount and distribution.

Different Associations Between the IREB2 Variants and Chronic Obstructive Pulmonary Disease Susceptibility

Background: Iron responsive element binding protein 2 (IREB2) variants may be involved in the pathogenesis of chronic obstructive pulmonary disease (COPD). Recently, many studies have been performed on IREB2 susceptibility variants, including rs2568494, rs2656069, rs10851906, rs12593229, and rs13180, associated with COPD. However, inconsistent findings have been reported. The aim of our research was to determine the association of IREB2 SNPs with COPD.

Methods: A comprehensive meta-analysis was performed to accurately estimate the association between IREB2 variants and COPD among four different genetic models.

Results: This meta-analysis included a total of 4,096 patients and 5,870 controls. Here, we investigated the 5 IREB2 variants to identify COPD risk. Our results indicate that rs2568494 was associated with an increased risk of COPD for the dominant model (AA+GA vs. GG: OR = 1.150, 95% CI: 1.5–1.304, P = 0.029); rs2656069 was associated with a decreased risk of COPD for the recessive model (GG vs. AA+AG: OR = 0.589, 95% CI: 0.440–0.789; P = 0.000), additive model (GG vs. AA: OR =0.641, 95% CI: 0.441–0.931; P = 0.020), and allele model (G vs. A: OR = 0.812, 95% CI: 0.668–0.988; P = 0.037); and rs10851906 was associated with a decreased risk of COPD for the recessive model (GG vs. AA+AG: OR = 0.732, 95% CI: 0.560–0.958; P = 0.023) and additive model (GG vs. AA: OR = 0.777, 95% CI: 0.637–0.947; P = 0.012).

Conclusion: Our findings suggest that the IREB2 rs2568494 minor alleles A may be a genetic factor in susceptibility to COPD. In addition, the minor alleles G of rs2656069 and rs10851906 appear to have a protective effect.

Genetic variants in FAM13A and IREB2 are associated with the susceptibility to COPD in a Chinese rural population: a case-control study

Background

Genome-wide association studies identified several genomic regions associated with the risk of chronic obstructive pulmonary disease (COPD), including the 4q22 and 15q25 regions. These regions contain the FAM13A and IREB2 genes, which have been associated with COPD but data are lacking for Chinese patients. The objective of the study was to identify new genetic variants in the FAM13A and IREB2 associated with COPD in Northwestern China.

Methods

This was a case-control study performed in the Ningxia Hui Autonomous Region between January 2014 and December 2016. Patients were grouped as COPD and controls based on FEV₁/FVC<70%. Seven tag single-nucleotide polymorphisms (SNPs) in the FAM13A and IREB2 genes were genotyped using the Agena MassARRAY platform. Logistic regression was used to determine the association between SNPs and COPD risk.

Results

rs17014601 in FAM13A was significantly associated with COPD in the additive (odds ratio [OR]=1.36, 95% confidence interval [CI]: 1.11-1.67, P=0.003), heterozygote (OR=1.76, 95% CI: 1.33-2.32, P=0.0001), and dominant (OR=1.67, 95% CI: 1.28-2.18, P=0.0001) models. Stratified analyses indicated that the risk was higher in never smokers. rs16969858 in IREB2 was significantly associated with COPD but in the univariate analysis only, and the multivariate analysis did not show any association.

Conclusion

The results suggest that the new variant rs17014601 in the FAM13A gene was significantly associated with COPD risk in a Chinese rural population. Additional studies are required to confirm the role of this variant in COPD development and progression.

FAM13A is a modifier gene of cystic fibrosis lung phenotype regulating rhoa activity, actin cytoskeleton dynamics and epithelial-mesenchymal transition

BACKGROUND

Cystic fibrosis (CF) lung disease severity is highly variable and dependent on several factors including genetic modifiers. Family with sequence similarity 13 member A (FAM13A) has been previously associated with lung function in the general population as well as in several chronic lung diseases, such as chronic obstructive pulmonary disease (COPD), we examined whether FAM13A is a modifier gene of CF lung phenotype. We also studied how FAM13A may contribute to the physiopathological mechanisms associated with CF.

METHODS

We investigated the association of FAM13A with lung function in CF French patients (n=1222) by SNP-wise analysis and Versatile Gene Based Association Study. We also analyzed the consequences of FAM13A knockdown in A549 cells and primary bronchial epithelial cells from CF patients.

RESULTS

We found that FAM13A is associated with lung function in CF patients. Utilizing lung epithelial A549 cells and primary human bronchial epithelial cells from CF patients we observed that IL-1β and TGFβ reduced FAM13A expression. Knockdown of FAM13A was associated with increased RhoA activity, induction of F-actin stress fibers and regulation of epithelial-mesenchymal transition markers such as E-cadherin, α-smooth muscle actin and vimentin.

CONCLUSION

Our data show that FAM13A is a modifier gene of CF lung phenotype regulating RhoA activity, actin cytoskeleton dynamics and epithelial-mesenchymal transition.

Revisiting asthma therapeutics: focus on WNT signal transduction

Asthma is a complex disease of the airways that develops as a consequence of both genetic and environmental factors. This interaction has highlighted genes important in early life, particularly those that control lung development, such as the Wingless/Integrase-1 (WNT) signalling pathway. Although aberrant WNT signalling is involved with an array of human conditions, it has received little attention within the context of asthma. Yet it is highly relevant, driving events involved with inflammation, airway remodelling, and airway hyper-responsiveness (AHR). In this review, we revisit asthma therapeutics by examining whether WNT signalling is a valid therapeutic target for asthma.

A Functional Variant rs6435156C > T in BMPR2 is Associated With Increased Risk of Chronic Obstructive Pulmonary Disease (COPD) in Southern Chinese Population

BACKGROUNDS

Bone morphogenetic protein receptor type 2 (BMPR2) signaling is anti-inflammatory. Decreased BMPR2 expression was seen in lung tissue from chronic obstructive pulmonary disease (COPD) patients.

METHODS

The selected single nucleotide polymorphisms (SNPs) in BMPR2 were genotyped with polymerase chain reaction (PCR) ligase detection reaction. The effects of SNPs on gene expression were analyzed with luciferase assays. The mRNA and protein expression levels of BMPR2 in peripheral blood mononuclear cells (PBMCs) from COPD patients were determined by quantitative PCR and western blotting, respectively.

FINDINGS

Two SNPs, rs6435156C > T and rs1048829G > T in the 3'-untranslated region (3'UTR) of BMPR2 were selected and genotyped in COPD case and healthy control subjects from southern Chinese population. Both of them were found associated with significantly increased COPD risk (adjusted odds ratio [OR] = 1.58 with 95% confidence interval [CI] = 1.14-2.15, P = 0.0056 for rs6435156C > T; adjusted OR = 1.47 and 95% CI = 1.10-1.97, P = 0.0092 for rs1048829G > T). Older age, cigarette smoking, family history of cancer and COPD were all factors that interacted with rs6435156C > T and rs1048829G > T causing increased COPD risk. Cigarette smokers with rs6435156 (CT + TT) or rs1048829 (GT + TT) were more susceptible to COPD than that with the rs6435156CC or rs1048829GG genotypes. In A549 human alveolar epithelial cells, luciferase reporter assays revealed that introduction of 3'UTR of BMPR2 plasmids carrying rs6435156T allele but not rs1048829T led to lower luciferase activity than the wild-type C or G alleles. Comparing to rs6435156CC, treatment with hsa-miR-20a mimics deceased whereas hsa-miR-20a inhibitor restored the luciferase reporter activity in cells transfected with constructs carrying rs6435156TT. BMPR2 mRNA and protein expressions were significantly lower in PBMCs from COPD smokers than that in non-smokers. COPD patients carrying rs6435156T allele had less BMPR2 expression in PBMCs.

INTERPRETATION

This study demonstrated that both rs6435156C > T and rs1048829G > T variants in BMPR2 contributed to increased susceptibility to COPD. The T variants of rs6435156 increased COPD risk likely by binding with hsa-miR-20a, thus leading to downregulated BMPR2 expression in lung epithelial and immune cells.

Association of IREB2 Gene rs2568494 Polymorphism with Risk of Chronic Obstructive Pulmonary Disease: A Meta-Analysis

Background

It is reported that the iron-responsive element-binding protein 2 (IREB2) gene rs2568494 polymorphism might be associated with COPD risk. The purpose of this meta-analysis was to collect all eligible studies to review the association between IREB2 gene rs2568494 polymorphism and susceptibility to COPD.

Material/Methods

We carried out a comprehensive document search of electronic databases of PubMed, MEDLIN, Web of Science, and included 4 eligible studies that examined the association between IREB2 rs2568494 polymorphism and COPD susceptibility. We performed a meta-analysis of these studies based on IREB2 rs2568494 genotypes.

Results

After meta-analysis with fixed or random effects, no significant associations were found under the heterozygote model (GG/GA; OR=0.908, 95%CI: 0.790–1.043; P=0.172), homozygote model (GG/AA; OR=0.880, 95%CI: 0.497–1.557; P=0.661), dominant model (GG/AA+GA; OR=0.941, 95%CI: 0.748–1.182; P=0.599), or allelic model (G/A; OR=0.953, 95%CI: 0.770–1.179; P=0.655). However, we found a significant correlation under the recessive model (AA/GA+GG; OR=1.384, 95%CI: 1.092–1.755; P=0.007).

Conclusions

The current results revealed that there was significant association between IREB2 gene rs2568494 polymorphism with susceptibility to COPD; the presence of allelic A might a genetic factor conferring susceptibility to COPD.

Candidate genes for COPD: current evidence and research

COPD is a common complex disease characterized by progressive airflow limitation. Several genome-wide association studies (GWASs) have discovered genes that are associated with COPD. Recently, candidate genes for COPD identified by GWASs include CHRNA3/5 (cholinergic nicotine receptor alpha 3/5), IREB2 (iron regulatory binding protein 2), HHIP (hedgehog-interacting protein), FAM13A (family with sequence similarity 13, member A), and AGER (advanced glycosylation end product–specific receptor). Their association with COPD susceptibility has been replicated in multiple populations. Since these candidate genes have not been considered in COPD, their pathological roles are still largely unknown. Herein, we review some evidences that they can be effective drug targets or serve as biomarkers for diagnosis or subtyping. However, more study is required to understand the functional roles of these candidate genes. Future research is needed to characterize the effect of genetic variants, validate gene function in humans and model systems, and elucidate the genes’ transcriptional and posttranscriptional regulatory mechanisms.

Susceptibility loci in lung cancer and COPD: association of IREB2 and FAM13A with pulmonary diseases

Genome-wide association studies have identified loci at 15q25 (IREB2) and 4q22 (FAM13A), associated with lung cancer (LC) and chronic obstructive pulmonary disease (COPD). The aim of our research was to determine the association of IREB2 and FAM13A SNPs with LC and severe/very severe COPD patients. We examined IREB2 variants (rs2568494, rs2656069, rs10851906, rs13180) and FAM13A (rs1903003, rs7671167, rs2869967) among 1.141 participants (468 LC, 149 COPD, 524 smoking controls). The frequency of the minor IREB2 rs2568494 AA genotype, was higher in LC vs controls (P = 0.0081, OR = 1.682). The FAM13A rs2869967 was associated with COPD (minor CC genotype: P = 0.0007, OR = 2.414). The rs1903003, rs7671167 FAM13A variants confer a protective effect on COPD (both P < 0.002, OR < 0.405). Haplotype-based tests identified an association of the IREB2 AAAT haplotype with LC (P = 0.0021, OR = 1.513) and FAM13A TTC with COPD (P = 0.0013, OR = 1.822). Cumulative genetic risk score analyses (CGRS), derived by adding risk alleles, revealed that the risk for COPD increased with the growing number of the FAM13A risk alleles. OR (95% CI) for carriers of ≥5 risk alleles reached 2.998 (1.8 to 4.97) compared to the controls. This study confirms that the IREB2 variants contribute to an increased risk of LC, whereas FAM13A predisposes to increased susceptibility to COPD.

Identification of FAM13A gene associated with the ratio of FEV1 to FVC in Korean population by genome-wide association studies including gene-environment interactions

Chronic obstructive pulmonary disease (COPD) is a complex, multifactorial disease. Although smoking is a main risk factor for obstructive impairment, not all smokers develop this critical disease. We conducted a genome-wide association study to identify the association between genetic variants and pulmonary function and also examined how these variants relate to lung impairment in accordance with smoking behaviors. Using two community-based cohorts, the Ansan cohort (n=4319) and the Ansung cohort (n=3674), in the Korean Genome Epidemiology Study, we analyzed the association between genetic variants (single-nucleotide polymorphisms and haplotypes) and the ratio of FEV1 to FVC (FEV1/FVC) using multivariate linear regression models. Similar analyses were conducted after stratification by smoking status. Four genome-wide significant signals in the FAM13A gene (the strongest signal at rs2609264, P=1.76 × 10(-7) in a combined set) were associated with FEV1/FVC. For the association with ratio, the effect size in the CTGA haplotype (risk haplotype) was -0.57% (s.e., 0.11; P=2.10 × 10(-7)) as compared with the TCAG haplotype (reference haplotype) in a combined set. There was also a significant interaction of FAM13A haplotypes with heavy smoking on FEV1/FVC (P for interaction=0.028). We confirmed the previously reported association of FAM13A in 4q22.1 with pulmonary function. The FAM13A haplotypes also interacted with heavy smoking to affect the risk of reduced pulmonary function.

Regulation of nuclear-cytoplasmic shuttling and function of Family with sequence similarity 13, member A (Fam13a), by B56-containing PP2As and Akt

Recent genome-wide association studies reveal that the FAM13A gene is associated with human lung function and a variety of lung diseases, including chronic obstructive pulmonary disease, asthma, lung cancer, and pulmonary fibrosis. The biological functions of Fam13a, however, have not been studied. In an effort to identify novel substrates of B56-containing PP2As, we found that B56-containing PP2As and Akt act antagonistically to control reversible phosphorylation of Fam13a on Ser-322. We show that Ser-322 phosphorylation acts as a molecular switch to control the subcellular distribution of Fam13a. Fam13a shuttles between the nucleus and cytoplasm. When Ser-322 is phosphorylated by Akt, the binding between Fam13a and 14-3-3 is enhanced, leading to cytoplasmic sequestration of Fam13a. B56-containing PP2As dephosphorylate phospho-Ser-322 and promote nuclear localization of Fam13a. We generated Fam13a-knockout mice. Fam13a-mutant mice are viable and healthy, indicating that Fam13a is dispensable for embryonic development and physiological functions in adult animals. Intriguingly, Fam13a has the ability to activate the Wnt pathway. Although Wnt signaling remains largely normal in Fam13a-knockout lungs, depletion of Fam13a in human lung cancer cells causes an obvious reduction in Wnt signaling activity. Our work provides important clues to elucidating the mechanism by which Fam13a may contribute to human lung diseases.

Moving beyond genetics: is FAM13A a major biological contributor in lung physiology and chronic lung diseases?

Variants in FAM13A have been found in genome-wide association studies (GWAS) to associate with lung function in the general population as well as in several common chronic lung diseases (CLD) such as chronic obstructive pulmonary disease (COPD), asthma, as well as in idiopathic interstitial pneumonias (IIP). The gene was cloned in 2004, yet the encoded protein has not been characterised and its function is unknown. The redundancy of its genetic contribution in CLD suggests a major function of this gene both in lung physiology and CLD. This review provides a brief summary of the current knowledge of FAM13A, and demonstrates the necessity to resolve its biological function besides its well accepted genetic contribution. Further interpretations of FAM13A variants may help in the understanding of CLD mechanisms and reveal opportunity for intervention.

Chronic Obstructive Pulmonary Disease Genetics: A Review of the Past and a Look Into the Future

Chronic obstructive pulmonary disease (COPD) affects over 10 million Americans.¹ This complex disorder demonstrates many different presentations in a wide variety of patients, and results from a combination of environmental exposures and genetic risk factors. Smoking alone does not result in COPD: not all smokers develop COPD and lung function decline among smokers is highly variable. There is growing evidence for genetic risk factors for COPD: early familial aggregation and linkage analysis studies strongly suggested genetic contributions to COPD, and recent genome-wide association studies have identified several genomic regions that are clearly related to COPD susceptibility. However, despite recent advances in COPD genetics, much of the heritability of COPD remains unexplained, and functional studies are only beginning to elucidate a role for the genetic associations that have been identified. Despite this, the future is bright for understanding the genetics of COPD. Improvements in COPD phenotyping, collaborations among COPD study cohorts, and novel integrative approaches to identifying genetic markers all promise to unravel much of this missing heritability and ultimately lead to improvements in our understanding of COPD susceptibility and treatment.

Heterogeneous phenotype in a family with the FERM domain-containing 7 gene R335X mutation

OBJECTIVE

Infantile nystagmus (IN) is characterized by bilateral involuntary, periodic, and predominantly ocular oscillations. In this article, we describe a mutation screen conducted on a 4-generation family in which 4 patients were affected with X-linked IN (XLIN).

DESIGN

Experimental study.

PARTICIPANTS

A 4-generation Chinese Han family including 4 symptomatic members with IN and 200 normal male controls.

METHODS

DNA was extracted from peripheral blood, and the FERM domain-containing 7 gene (FRMD7) was amplified on DNA samples of all the available family members. The mutation screen was conducted by performing direct DNA sequencing.

RESULTS

A nonsense mutation (R335X) in the FRMD7 gene was identified in 4 male patients and an asymptomatic female member.

CONCLUSIONS

Although the R335X mutation in the FRMD7 gene has been previously described, the clinical features, including both disease penetrance and severity, among individuals with FRMD7 mutation in our family vary greatly. One female member with the heterozygous R335X mutation had no clinical manifestation of the disease. This incomplete penetrance suggests that random X-chromosome inactivation may play a role in the pathogenesis of IN, and that loss of functional FRMD7 may account for the development of this disorder. Our findings may be helpful in the genetic counseling of patients with nystagmus.

Spherical Topic Models for Imaging Phenotype Discovery in Genetic Studies

In this paper, we use Spherical Topic Models to discover the latent structure of lung disease. This method can be widely employed when a measurement for each subject is provided as a normalized histogram of relevant features. In this paper, the resulting descriptors are used as phenotypes to identify genetic markers associated with the Chronic Obstructive Pulmonary Disease (COPD). Features extracted from images capture the heterogeneity of the disease and therefore promise to improve detection of relevant genetic variants in Genome Wide Association Studies (GWAS). Our generative model is based on normalized histograms of image intensity of each subject and it can be readily extended to other forms of features as long as they are provided as normalized histograms. The resulting algorithm represents the intensity distribution as a combination of meaningful latent factors and mixing co-efficients that can be used for genetic association analysis. This approach is motivated by a clinical hypothesis that COPD symptoms are caused by multiple coexisting disease processes. Our experiments show that the new features enhance the previously detected signal on chromosome 15 with respect to standard respiratory and imaging measurements.

Elevated serum iron is a potent biomarker for spirometric resistance to cigarette smoke among Japanese males: the Takahata study

Chronic obstructive pulmonary disease is a common disability among elderly subjects with a heavy cigarette smoking habit. In contrast to the population that is susceptible to smoking, in whom pulmonary function worsens with the length of exposure to cigarette smoke, there are elderly individuals whose pulmonary function is not impaired. However, to date, the characteristics of this resistant smoking population have not been investigated. We aimed to identify a biomarker in individuals in whom lung health is maintained despite smoking. Blood sampling and spirometry were performed on 3,257 subjects who participated in a community-based annual health check in Takahata, Japan, from 2004 to 2006. We selected 117 elderly smokers (age ≥70, Brinkman index ≥600, smoking years ≥30). The 'smoking resistant' group met the following criteria: FEV1/FVC ≥0.7, and FEV1%predicted ≥80. Spirometry was re-evaluated in 147 male, current smokers in 2009. Baseline serum iron (sFe) levels were higher in the smoke resistant group compared with the non-resistant group. In those with low sFe levels, FEV1/FVC was reduced in male subjects. These spirometric measures were positively associated with sFe levels in men. Multiple linear regression analysis revealed that sFe levels were predictive for spirometric values, independent of other clinical factors. In addition, sFe levels were predictive for a decline in FEV1.Serum iron levels may be a biomarker for the spirometric susceptibility of individuals to cigarette smoke.

Relationship between plasma fibrinogen levels and pulmonary function in the japanese population: the Takahata study

BACKGROUND

Plasma fibrinogen is considered a biomarker of respiratory disease, owing to the relationship between plasma fibrinogen and pulmonary function established in Western populations. However, such a relationship has not yet been confirmed in an Asian population. We assessed this relationship in the general Japanese population.

METHODS

Totally, 3,257 men and women aged ≥40 years who participated in a community-based annual health checkup in Takahata, Japan, from 2004 to 2006, underwent spirometry, and their plasma fibrinogen levels were determined.

RESULTS

We found an inverse relationship between spirometric measures (percent predicted forced vital capacity [%FVC] and forced expiratory volume in 1s [%FEV1], and FEV1/FVC) and plasma fibrinogen levels in men, but not in women. The plasma fibrinogen levels were significantly higher in subjects with restrictive, obstructive, and mixed ventilatory disorders than in those with normal spirometry results. Multiple linear regression analysis revealed that in men, plasma fibrinogen levels were predictive for %FVC and %FEV1 (independent of age, body mass index, and cigarette smoking) but not for FEV1/FVC.

CONCLUSIONS

Plasma fibrinogen was significantly associated with pulmonary function in Japanese men, and as such, plasma fibrinogen might be a potent biomarker for pulmonary dysfunction in men.

Association of FAM13A polymorphisms with COPD and COPD-related phenotypes in Han Chinese

OBJECTIVES

Genome-wide association studies (GWAS) and integrative genomics approaches have demonstrated significant associations between chronic obstructive pulmonary disease (COPD) and FAM13A polymorphisms in non-Asian populations. The aim of this study was to investigate whether FAM13A polymorphisms would be associated with COPD susceptibility and COPD-related phenotypes in a Chinese Han population.

METHODS

Seven single nucleotide polymorphisms (SNPs) (rs7671167, rs10007590, rs2869966, rs2869967, rs2045517, rs1903003, rs6830970) in FAM13A gene were genotyped in a case-control study (680 COPD patients and 687 controls). Allele frequencies and genotype distributions were compared between patients and controls. To estimate the strength of association, odds ratios (OR) (with 95% CI) were calculated and potential confounding variables were tested by using logistic regression analysis.

RESULTS

Statistical analysis revealed that SNP rs7671167 was associated with COPD in former smokers with adjusted P-value of 0.026. Five SNPs (rs7671167, rs2869966, rs2869967, rs2045517, and rs6830970) were associated with FEV1/FVC ratio in the entire cohort and rs6830970 was associated with FEV1/FVC ratio in COPD cases (P range 0.003-0.034). Borderline associations with FEV1/FVC ratio were found for rs2869966, rs2869967 and rs2045517 among cases (P=0.05). Six SNPs (rs7671167, rs2869966, rs2869967, rs2045517, rs1903003, rs6830970) showed strong linkage disequilibrium (r(2) ≥ 0.9). Four major haplotypes were observed but showed no significant difference between case and control groups (P=0.2356, 0.1273, 0.6266 and 0.3006 respectively).

CONCLUSIONS

The current study suggests that the FAM13A locus might be a contributor to COPD susceptibility in Chinese Han population.

Association of IREB2 and CHRNA3/5 polymorphisms with COPD and COPD-related phenotypes in a Chinese Han population

Genome-wide association studies and integrative genomics approaches have demonstrated significant associations between chronic obstructive pulmonary disease (COPD) and single-nucleotide polymorphisms (SNPs) in the chromosome 15q25 region that includes iron-responsive element binding protein 2 gene (IREB2) and CHRNA3/5 in non-Asian populations. We investigated whether IREB2 and CHRNA3/5 polymorphisms would be associated with COPD susceptibility and COPD-related phenotypes in a Chinese Han population. Eight SNPs (rs2568494, rs2656069, rs10851906, rs1964678, rs12593229, rs965604, rs13180, rs17483929) in IREB2 gene and four SNPs (rs16969968, rs1051730, rs938682, rs8034191) in or near CHRNA3/5 locus were genotyped in a case-control study (680 COPD patients and 687 controls). No significant associations were found between any of the SNPs and COPD in either former-smokers or current-smokers. Two SNPs (rs2656069 and rs10851906) in IREB2 were associated with COPD (P=0.045 and 0.032, respectively) in non-smoker. Four SNPs (rs1964678, rs12593229, rs965604 and rs13180) in IREB2 were associated with forced expiratory volume in 1 s (FEV(1))% predicted and three SNPs (rs16969968, rs8034191 and rs1051730) in CHRNA3/5 were both associated with FEV(1)% predicted and FEV(1)/FVC in COPD cases (P range 0.007-0.050). The SNP rs8034191 near CHRNA3/5 locus was significantly associated with pack-years of smoking in COPD patients (P=0.033). We demonstrated IREB2 polymorphisms were associated with COPD in non-smoking subjects, and the effect of IREB2 gene on COPD may be independent from smoking and independent from CHRNA3/5 gene cluster. Besides, we confirmed that SNPs in these two gene loci were associated with pulmonary function and CHRNA3/5 polymorphism was associated with pack-year of smoking in COPD patients in the Chinese Han population.