The angiotensin-converting enzyme insertion/deletion and the endothelin -134 3A/4A gene polymorphisms in patients with chronic plaque psoriasis

The Relationship Between Angiotensin-Converting Enzyme Gene I/D Polymorphism and Psoriasis, Including Psoriasis with Comorbid Hypertension and Diabetes

Objective

The relationship between angiotensin-converting enzyme (ACE) insertion/deletion (I/D) gene polymorphism and psoriasis remains unclear. This study aims to analyze the association between ACE gene I/D polymorphism and the risk of psoriasis vulgaris in the Chinese Han population and to examine the correlation between ACE gene I/D polymorphism and psoriasis with comorbid hypertension and diabetes.

Methods

A total of 358 patients with psoriasis vulgaris and 347 age- and sex-matched healthy volunteers from the Chinese Han population were selected. Clinical data, including blood pressure and fasting blood glucose, were collected from the patients. The ACE gene I/D polymorphism was analyzed using polymerase chain reaction (PCR). The association between ACE gene I/D polymorphism and psoriasis vulgaris, as well as comorbid hypertension and diabetes, was analyzed using the Pearson χ²-test.

Results

The frequency of the ACE II genotype (OR = 1.84, 95% CI = 1.30, 2.61; P < 0.01) and the I allele (OR = 1.51, 95% CI = 1.22, 1.86; P < 0.01) was significantly higher in psoriasis patients compared to the control group. Conversely, the frequency of the ACE DD genotype (OR = 0.62, 95% CI = 0.44, 0.87; P < 0.01) and the D allele (OR = 0.66, 95% CI = 0.54, 0.82; P < 0.01) was significantly lower in psoriasis patients compared to the control group. No statistically significant differences were observed when stratified by blood pressure and blood glucose abnormalities (P > 0.05).

Conclusion

The ACE II genotype and I allele are risk factors for psoriasis vulgaris in the Northern Chinese Han population.

The association between ACE inhibitors and psoriasis based on the drug-targeted Mendelian randomization and real-world pharmacovigilance analyses

BACKGROUND

Although a growing number of observational studies suggest that angiotensin-converting enzyme inhibitors (ACEIs) intake may be a risk factor for psoriasis, evidence is still insufficient to draw definitive conclusions.

RESEARCH DESIGN AND METHODS

Drug-targeted Mendelian randomization (DTMR) was used to analyze the causality between genetic proxied ACEIs and psoriasis. Furthermore, we performed a disproportionality analysis based on the FDA adverse event reporting system (FAERS) database to identify more suspicious subclasses of ACEIs.

RESULTS

Using two kinds of genetic proxy instruments, the present DTMR research identified genetic proxied ACEIs as risk factors for psoriasis. Furthermore, our disproportionality analysis revealed that ramipril, trandolapril, perindopril, lisinopril, and enalapril were associated with the risk of psoriasis, which validates and refines the findings of the DTMR.

CONCLUSIONS

Our integrative study verified that ACEIs, especially ramipril, trandolapril, perindopril, lisinopril, and enalapril, tended to increase the risk of psoriasis statistically.

The role of vasoactive peptides in skin homeostasis-focus on adiponectin and the kallikrein-kinin system

Vasoactive peptides often serve a multitude of functions aside from their direct effects on vasodynamics. This article will review the existing literature on two vasoactive peptides and their involvement in skin homeostasis: adiponectin and-as the main representative of the kallikrein-kinin system-bradykinin. Adiponectin is the most abundantly expressed adipokine in the human organism, where it is mainly localized in fat depots including subcutaneous adipose tissue, from where adiponectin can exert paracrine effects. The involvement of adiponectin in skin homeostasis is supported by a number of studies reporting the effects of adiponectin in isolated human keratinocytes, sebocytes, fibroblasts, melanocytes, and immune cells. Regarding skin pathology, the potential involvement of adiponectin in psoriasis, atopic dermatitis, scleroderma, keloid, and melanogenesis is discussed in this article. The kallikrein-kinin system is composed of a variety of enzymes and peptides, most of which have been identified to be expressed in the skin. This also includes the expression of bradykinin receptors on most skin cells. Bradykinin is one of the very few hormones that is targeted by treatment in routine clinical use in dermatology-in this case for the treatment of hereditary angioedema. The potential involvement of bradykinin in wound healing, psoriasis, and melanoma is further discussed in this article. This review concludes with a call for additional preclinical and clinical studies to further explore the therapeutic potential of adiponectin supplementation (for psoriasis, atopic dermatitis, wound healing, scleroderma, and keloid) or pharmacological interference with the kallikrein-kinin system (for wound healing, psoriasis, and melanoma).

Psoriasis and Cardiometabolic Diseases: Shared Genetic and Molecular Pathways

A convincing deal of evidence supports the fact that severe psoriasis is associated with cardiovascular diseases. However, the precise underlying mechanisms linking psoriasis and cardiovascular diseases are not well defined. Psoriasis shares common pathophysiologic mechanisms with atherosclerosis and cardiovascular (CV) risk factors. In particular, polymorphism in the IL-23R and IL-23 genes, as well as other genes involved in lipid and fatty-acid metabolism, renin-angiotensin system and endothelial function, have been described in patients with psoriasis and with cardiovascular risk factors. Moreover, systemic inflammation in patients with psoriasis, including elevated serum proinflammatory cytokines (e.g., TNF-α, IL-17, and IL-23) may contribute to an increased risk of atherosclerosis, hypertension, alteration of serum lipid composition, and insulin resistance. The nonlinear and intricate interplay among various factors, impacting the molecular pathways in different cell types, probably contributes to the development of psoriasis and cardiovascular disease (CVD). Future research should, therefore, aim to fully unravel shared and differential molecular pathways underpinning the association between psoriasis and CVD.

Genetic variants affecting chemical mediated skin immunotoxicity

The skin is an immune-competent organ and this function may be impaired by exposure to chemicals, which may ultimately result in immune-mediated dermal disorders. Interindividual variability to chemical-induced skin immune reactions is associated with intrinsic individual characteristics and their genomes. In the last 30-40 years, several genes influencing susceptibility to skin immune reactions were identified. The aim of this review is to provide information regarding common genetic variations affecting skin immunotoxicity. The polymorphisms selected for this review are related to xenobiotic-metabolizing enzymes (CYPA1 and CYPB1 genes), antioxidant defense (GSTM1, GSTT1, and GSTP1 genes), aryl hydrocarbon receptor signaling pathway (AHR and ARNT genes), skin barrier function transepidermal water loss (FLG, CASP14, and SPINK5 genes), inflammation (TNF, IL10, IL6, IL18, IL31, and TSLP genes), major histocompatibility complex (MHC) and neuroendocrine system peptides (CALCA, TRPV1, ACE genes). These genes present variants associated with skin immune responses and diseases, as well as variants associated with protecting skin immune homeostasis following chemical exposure. The molecular and association studies focusing on these genetic variants may elucidate their functional consequences and contribution in the susceptibility to skin immunotoxicity. Providing information on how genetic variations affect the skin immune system may reduce uncertainties in estimating chemical hazards/risks for human health in the future.

Analysis of the Potential Genetic Links between Psoriasis and Cardiovascular Risk Factors

Cardiovascular risk factors are one of the most common comorbidities in psoriasis. A higher prevalence of hypertension, insulin resistance and type 2 diabetes, dyslipidemia, obesity, metabolic syndrome, depression, as well as cardiovascular disease was confirmed in psoriatic patients in comparison to the general population. Data suggest that psoriasis and systemic inflammatory disorders may originate from the pleiotropic interactions with many genetic pathways. In this review, the authors present the current state of knowledge on the potential genetic links between psoriasis and cardiovascular risk factors. The understanding of the processes linking psoriasis with cardiovascular risk factors can lead to improvement of psoriasis management in the future.

The Multifaceted Nature of Aminopeptidases ERAP1, ERAP2, and LNPEP: From Evolution to Disease

In the human genome, the aminopeptidases ERAP1, ERAP2 and LNPEP lie contiguously on chromosome 5. They share sequence homology, functions and associations with immune-mediated diseases. By analyzing their multifaceted activities as well as their expression in the zoological scale, we suggest here that the progenitor of the three aminopeptidases might be LNPEP from which the other two aminopeptidases could have derived by gene duplications. We also propose that their functions are partially redundant. More precisely, the evolutionary story of the three aminopeptidases might have been dictated by their role in regulating the renin–angiotensin system, which requires their controlled and coordinated expression. This hypothesis is supported by the many species that lack one or the other gene as well as by the lack of ERAP2 in rodents and a null expression in 25% of humans. Finally, we speculate that their role in antigen presentation has been acquired later on during evolution. They have therefore been diversified between those residing in the ER, ERAP1 and ERAP2, whose role is to refine the MHC-I peptidomes, and LNPEP, mostly present in the endosomal vesicles where it can contribute to antigen cross-presentation or move to the cell membrane as receptor for angiotensin IV. Their association with autoinflammatory/autoimmune diseases can therefore be two-fold: as “contributors” to the shaping of the immune-peptidomes as well as to the regulation of the vascular response.

Angiotensin converting enzyme: A review on expression profile and its association with human disorders with special focus on SARS-CoV-2 infection

Angiotensin-converting enzyme (ACE) and its homologue, ACE2, have been mostly associated with hypertensive disorder. However, recent pandemia of SARS-CoV-2 has put these proteins at the center of attention, as this virus has been shown to exploit ACE2 protein to enter cells. Clear difference in the response of affected patients to this virus has urged researchers to find the molecular basis and pathophysiology of the cell response to this virus. Different levels of expression and function of ACE proteins, underlying disorders, consumption of certain medications and the existence of certain genomic variants within ACE genes are possible explanations for the observed difference in the response of individuals to the SARS-CoV-2 infection. In the current review, we discuss the putative mechanisms for this observation.

Angiotensin-converting enzyme gene insertion/deletion polymorphism and susceptibility to psoriasis: a systematic review and meta-analysis

BACKGROUND

Psoriasis is a multifactorial disorder, impacted by both genetic and environmental factors. Herein, a meta-analysis assessed the association of angiotensin-converting enzyme gene insertion/deletion (ACE I/D) polymorphism and psoriasis susceptibility.

METHODS

A systematic search was used in databases of PubMed/Medline, Scopus, Web of Science, and Cochrane Library up to January 2019 without language restriction. A dichotomous analysis was carried out by RevMan 5.3 using crude odds ratio (OR) and 95% confidence interval (CI) to investigate the association between ACE I/D polymorphisms and the risk of psoriasis. A funnel plot analysis was used by CMA 2.0 to estimate a significant existence of publication bias.

RESULTS

Out of 61 studies retrieved from the databases, 16 studies were included in the meta-analysis. The pooled ORs for models of D vs. I, DD vs. II, ID vs. II, ID + DD vs. II, and DD vs. II + ID genotypes were 0.96 [95%CI: 0.82, 1.12; P = 0.58], 0.99 [95%CI, 0.73, 1.36; P = 0.96], 0.81 [95%CI, 0.72, 0.91; p: 0.0003], 0.91 [95%CI, 0.73, 1.13; P = 0.40], and 1.05 [95%CI, 0.85, 1.30; P = 0.68], respectively. A significant difference between ACE polymorphisms in patients with/without family history for the disease [OR = 1.44; 95%CI: 1.24, 1.67; P < 0.001] and also in patients mild/severe psoriasis [OR = 0.70; 95%CI: 0.55, 0.88; P = 0.002] was identified.

CONCLUSION

The results of the meta-analysis showed that ACE I/D polymorphism may be associated with psoriasis susceptibility, while ID genotype seemed to have a protective role in Caucasian patients affected by psoriatic arthritis and in studies with hospital-based controls.

Angiotensin-converting enzyme insertion/deletion (rs106180) and angiotensin type 1 receptor A1166 C (rs106165) genotypes and psoriasis: Correlation with cellular immunity, lipid profile, and oxidative stress markers

Psoriasis is a chronic inflammatory skin condition and angiotensin-converting enzyme (ACE) is a key circulating enzyme converting angiotensin (Ang) I to the vasoactive peptide Ang II. The exact role of ACE insertion (I)/deletion (D) polymorphism (rs106180) in psoriasis is not clear. We aimed to examine whether the ACE I/D and Ang II type 1 receptor (AT1R) A₁₁₆₆ C-polymorphisms (rs106165), lipid profile, and stress oxidative are associated with susceptibility to psoriasis. One hundred patients with psoriasis and 100 sex- and age-matched unrelated healthy controls were recruited for this case-control study. ACE I/D and AT1R A₁₁₆₆ C polymorphisms were identified by the polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism, respectively, malondialdehyde (MDA) was detected by the high-performance liquid chromatography, serum arylesterase (ARE) activity of paraoxonase and catalase activities were detected by the spectrophotometry, superoxide dismutase (SOD) activity and vascular adhesion protein (VAP)-1 were measured by ELISA. The presence of C allele of AT1R A₁₁₆₆ C and I allele of ACE considerably increased the risk of psoriasis by 6.42-fold (P < 0.001). The distribution of II-genotype of ACE was significantly higher in psoriasis patients than in control group and increased the risk of disease by 3.11-times (P = 0.023). The higher levels of MDA in patients and the higher activity of SOD, ARE, and CAT was observed in healthy controls with I/D+I/I-genotype of ACE I/D. This study for the first time demonstrated that the ACE I/D and AT1R A ₁₁₆₆ C genes polymorphisms robustly increases the risk of developing psoriasis in population from west of Iran. In addition, these individuals had significantly higher VAP-1 and MDA concentration and lower enzymatic and nonenzymatic antioxidant-status, suggesting that psoriatic patients carrying C allele of AT1R₁₁₆₆ polymorphism may be more susceptible to cardiovascular disease and myocardial infarction compared with A allele.

An Extensive Study of the Functional Polymorphisms of Kinin-Kallikrein System in Rheumatoid Arthritis Susceptibility

Objectives

This study aims to examine the following functional polymorphisms in rheumatoid arthritis (RA) susceptibility: (i) the 587C>T of kininogen gene, (ii) the 287 bp Alu repeat insertion of angiotensin converting enzyme gene, (iii) the 9 bp insertion of bradykinin receptor 2 gene, (iv) the -58T>C of bradykinin receptor 2 gene, and (v) the -699G>C of bradykinin receptor 1 gene.

Patients and methods

The study included 136 RA patients (27 males; 109 females; mean age 60.8 years; range 39 to 75 years) and 149 ethnic matching controls (30 males, 119 females; mean age 56.2 years; range 35 to 78 years). Polymerase chain reaction coupled with restriction assay was performed for 587C>T, -58T>C, and -699G>C.

Results

Rheumatoid arthritis patients and controls carried the wild type allele of 587C>T; therefore, produced the high molecular weight kininogen. No significant difference was observed in genotype or allele distribution of the studied functional polymorphisms between RA patients and controls.

Conclusion

Kinin-kallikrein system related genes might not be major RA susceptibility loci.

Psoriasis as a cardiovascular risk factor: updates and algorithmic approach

Although psoriasis is predominantly a chronic inflammatory skin disorder, it has been known to be associated with cardiovascular disease. Patients with psoriasis, particularly with moderate to severe forms, present an increased rate of cardiovascular mortality, myocardial infarction and stroke. However the pathophysiology of the relationship between psoriasis and cardiovascular risk and comorbidities has not yet completely known. Chronic inflammation may be considered a solid link between psoriasis and related cardiovascular events. Several cytokines and inflammatory cells play a pivotal role in the development of psoriatic lesions, resulting in angiogenesis and endothelial dysfunction. Furthermore, the imbalance between oxidative stress and antioxidant mechanisms in psoriatic patients may contribute to explain the pathogenesis of increased reactive oxygen species and the formation of atherosclerotic plaque. Other mechanistic pathways which may be involved in this relationship include cardiovascular effects of medications, a common genetic background and a higher prevalence of cardiovascular risk factors, which are often under-diagnosed and under-treated in psoriatic patients. Indeed, the early detection of specific markers of cardiovascular impairment, such as N-terminal pro B-type natriuretic peptide, homocysteine and YKL-40, may enable psoriatic patients at higher cardiovascular risk to be identified as soon as possible. This review examines the increased cardiovascular risk profile and high prevalence of cardiovascular disease associated with psoriasis, focusing on pathogenic links between psoriasis and atherosclerosis, serological markers of cardiovascular involvement and the implications of antipsoriatic therapies on cardiovascular risk and proposes a flow chart, that every dermatologist should follow to screen psoriatic patients.

Polymorphisms Associated with Age at Onset in Patients with Moderate-to-Severe Plaque Psoriasis

Psoriasis is a chronic skin disease in which genetics play a major role. Although many genome-wide association studies have been performed in psoriasis, knowledge of the age at onset remains limited. Therefore, we analyzed 173 single-nucleotide polymorphisms in genes associated with psoriasis and other autoimmune diseases in patients with moderate-to-severe plaque psoriasis type I (early-onset, <40 years) or type II (late-onset, ≥40 years) and healthy controls. Moreover, we performed a comparison between patients with type I psoriasis and patients with type II psoriasis. Our comparison of a stratified population with type I psoriasis (n = 155) and healthy controls (N = 197) is the first to reveal a relationship between the CLMN, FBXL19, CCL4L, C17orf51, TYK2, IL13, SLC22A4, CDKAL1, and HLA-B/MICA genes. When we compared type I psoriasis with type II psoriasis (N = 36), we found a significant association between age at onset and the genes PSORS6, TNF-α, FCGR2A, TNFR1, CD226, HLA-C, TNFAIP3, and CCHCR1. Moreover, we replicated the association between rs12191877 (HLA-C) and type I psoriasis and between type I and type II psoriasis. Our findings highlight the role of genetics in age of onset of psoriasis.

Association of Angiotensin-Converting Enzyme (ACE) Gene Polymorphism with Inflammation and Cellular Cytotoxicity in Vitiligo Patients

BACKGROUND

Vitiligo is a disorder with profound heterogeneity in its aetio-pathophysiology. Angiotensin converting enzyme (ACE) plays an important role in the physiology of the vasculature, blood pressure and inflammation. An insertion/deletion (I/D) polymorphism of the ACE gene was reported be associated with the development of vitiligo.

OBJECTIVE

Our aim was to evaluate the ACE I/D polymorphism in vitiligo patients and controls. Our second aim was to find a possible association between ACE gene polymorphism and inflammatory mediators (as interleukin (IL)-6) and/or cellular cytotoxicity induced by serum nitrite (as a breakdown product of the cytotoxic nitric oxide) in vitiligo patients.

METHODS

This case-control study included 74 vitiligo patients and 75 apparently healthy controls. The distribution of ACE gene I/D genotype was investigated using PCR. Serum ACE, IL-6 and nitrite were measured by colorimetric method, ELISA and Griess assay respectively.

RESULTS

The ACE allele frequency was significantly different between vitiligo patients and healthy controls (P = 0.026). However there was no significant difference between the ACE genotyping frequency in both groups (P = 0.115). There were statistically significant higher VIDA score (P = 0.007), and serum IL-6 (P < 0.001) in patients with the DD genotype when compared to other genotypes. Serum nitrite in patients with the DD genotype was significantly higher (P = 0.007) when compared to patients with II genotype. Serum levels of ACE, IL-6 and nitrite in vitiligo patients were statistically significantly higher than those in controls.

CONCLUSION

As a conclusion, ACE gene polymorphism might grant susceptibility to develop vitiligo. Serum IL-6 and nitrite levels might have an important role in the pathogenesis of vitiligo. Targeting these two factors might have an implication in the treatment of some resistant cases.

Evaluation of the association between CD143 gene polymorphism and psoriasis

Increased CD143 activity has been detected in various skin tissues, and this increase is partially caused by the intronic ID polymorphism. The genetic contribution of CD143 ID polymorphism to the progression of psoriasis, the commonest skin disease, has been extensively investigated, but reported with inconsistent results. The aim of this work was to gain new insights to shed light on the association between CD143 ID polymorphism and psoriasis risk. We systematically identified the studies examining the association of CD143 ID polymorphism with psoriasis risk. A meta-analysis combining data from all eligible studies was carried out. To evaluate the genetic association, we calculated odds ratio (OR) and its 95 % confidence intervals (CIs) for both genotypic models and allelic model. The final pooling dataset comprised ten studies. Meta-analysis of total samples did not suggest a notable association with psoriasis risk. However, subgroup analysis by ethnicity revealed a statistically significant association in East Asian samples (DD + ID vs. II: OR 0.86, 95 % CI 0.75-0.99, P heterogeneity = 0.970; DD vs. ID: OR 0.85, 95 % CI 0.73-0.99, P heterogeneity = 0.868; D vs. I: OR 0.86, 95 % CI 0.76-0.97, P heterogeneity = 0.994). This meta-analysis demonstrated that the presence of CD143 ID polymorphism may modify the risk of psoriasis in individuals with East Asian ancestry.

G-231A and G+70C Polymorphisms of Endothelin Receptor Type-A Gene could Affect the Psoriasis Area and Severity Index Score and Endothelin 1 Levels

Background:

The etiopathogenesis of psoriasis has not been clearly elucidated although the role of chronic inflammation, imbalance between pro- and anti-inflammatory cytokines, and many immunological events have been established. Endothelin 1 (EDN1) and endothelin receptor type-A (EDNRA) are implicated in the inflammatory process. The relationships between EDN1 and EDNRA polymorphisms with several diseases have been found.

Aims and Objectives:

This study examined the possible association of EDN1 (G5665T and T-1370G) and EDNRA (G-231A and G + 70C) single nucleotide polymorphisms (SNPs) with the occurence of psoriasis, and evaluated the relationship between genotypes and clinical/laboratory manifestation of psoriasis.

Materials and Methods:

We analyzed genotype and allele distributions of the above-mentioned polymorphisms in 151 patients with psoriasis and 152 healthy controls by real-time PCR combined with melting curve analysis.

Results:

We did not find significant differences in the genotype and allele distributions of EDN1 T-1370G, EDNRA G-231A, and EDNRA G+70C polymorphisms between patients with psoriasis and healthy controls. Psoriasis area and severity index (PASI) score of EDNRA –231 polymorphic A allele carrying subjects (AA and AA + AG) was higher than that of wild homozygotes (P = 0.044 and P = 0.027, respectively). In addition, EDN1 levels in EDNRA+70 polymorphic C allele carriers (CC + CG) were elevated when compared with GG genotype; however, the difference was at borderline significance (P = 0.05).

Conclusion:

Although there were no associations between studied polymorphisms and psoriasis susceptibility, the PASI score and EDN1 levels seem to be affected by EDNRA G-231A and G + 70C polymorphisms.

Identification of a missense variant in LNPEP that confers psoriasis risk

Psoriasis is a chronic inflammatory disease with a complex genetic architecture. To further advance gene discovery, we extended our genome-wide association study data set of 1,139 cases and 2,234 controls and replicated two independent cohorts of 7,200 cases and 10,491 controls. We identified the missense variant rs2303138 (p.Ala763Thr) within the LNPEP gene associated with psoriasis (Pcombined=1.83 × 10(-13), odds ratio=1.16) and validated four previously reported genes: IL28RA, NFKBIA, TRAF3IP2, and CARD14 (9.74 × 10(-11)P9.37 × 10(-5)), which confirmed the involvement of the nuclear factor-κB signaling pathway in psoriasis pathogenesis. LNPEP, also named insulin-responsive aminopeptidase, was identified as an angiotensin IV receptor. Protein function prediction suggested that this missense variant of LNPEP was most likely deleterious. Expression analysis showed that LNPEP was significantly downregulated in psoriatic lesions compared with the control skin (P=1.44 × 10(-6)) and uninvolved patient skin (P=2.95 × 10(-4)). Pathway analysis indicated that LNPEP was involved in the renin-angiotensin system, which also has a key role in cardiovascular disease and diabetes. These results provided genetic evidence that psoriasis might share common mechanisms with hypertension and diabetes, which was consistent with clinical observations. Our study identified a genetic susceptibility factor and provided genetic evidence of insight into psoriasis pathogenesis with the involvement of the renin-angiotensin system pathway.

Angiotensin-converting enzyme gene polymorphisms and the risk of psoriasis: a meta-analysis

BACKGROUND

The gene coding for angiotensin-converting enzyme (ACE) has been reported to be associated with the development of psoriasis.

AIM

To evaluate the association of psoriasis risk and ACE polymorphisms.

METHODS

We carried out a retrieval of studies that explored associations between ACE polymorphism and psoriasis, and analysed the genotype frequencies.

RESULTS

In total, 8 studies with 1242 patients and 1646 controls were included. The genotype frequencies in all studies were in Hardy-Weinberg equilibrium. After pooling all studies, the results indicated that the I/I genotype was associated with risk of psoriasis (OR = 1.41, 95% CI 1.11-1.80, P = 0.005), whereas the I/D genotype may decrease the risk of psoriasis (OR = 0.71, 95% CI 0.56-0.90, P = 0.005) in Asian, but not in white populations.

CONCLUSIONS

Our study suggests that ACE polymorphism are associated with the risk of psoriasis in Asians, especially the I/I genotype and I allele. Further studies are needed to confirm our results.

Angiotensin-converting enzyme insertion/deletion polymorphism and susceptibility to psoriasis in a Chinese population

INTRODUCTION

The relationship between the angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism and psoriasis has previously been studied mainly in Caucasians and only once in Asians. The aim of this study is to evaluate the association between the ACE I/D polymorphism and the risk of psoriasis in a Chinese population.

MATERIALS AND METHODS

The study population consisted of 668 psoriasis patients and 668 matched control subjects. The ACE I/D gene polymorphism was analyzed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

RESULTS

The frequency of the ACE II genotype (odds ratio (OR) = 1.32, 95% confidence interval (CI) = 1.06, 1.63; P = 0.01) and I allele (OR = 1.25, 95% CI = 1.06, 1.48; P = 0.01) in patients with psoriasis was significantly higher than that in the control group. And the D allele frequency in patients with psoriasis was significantly lower (OR = 0.80, 95% CI = 0.68, 0.95; P = 0.01) than that in the control group. When stratified by family history, the frequency of the DD genotype was marginally significantly lower in patients with a positive family history of psoriasis (familial psoriasis) than in those with negative (sporadic psoriasis) (OR = 0.47, 95% CI = 0.23, 0.97; P = 0.04). When stratified by onset of the disease, type of psoriasis and the severity of psoriasis, no statistically significant result was observed.

CONCLUSION

Our study suggested that the ACE II genotype and I allele might confer susceptibility to psoriasis in a Chinese population.

Associations between the insertion/deletion polymorphism of the angiotensin-converting enzyme and susceptibility to aortic aneurysms: A meta-analysis

INTRODUCTION

The purpose of this study is to examine whether the insertion (I) and deletion (D) polymorphism of the angiotensin-converting enzyme (ACE) confers susceptibility to aortic aneurysms (AAs).

MATERIALS AND METHODS

A meta-analysis was conducted on the associations between the ACE I/D polymorphism and all AAs and abdominal aortic aneurysms (AAAs).

RESULTS

Ten studies consisting of 2784 cases and 2682 controls were available for the meta-analysis. Meta-analysis showed a significant association between the D allele and all types of AA (OR 1.378, 95% CI 1.103-1.723, p = 0.005) and AAA (OR 1.274, 95% CI 1.004-1.617, p = 0.046). Meta-analysis of both the DD genotype and the DD vs. II genotype showed an association with AAAs. Stratification by ethnicity indicated an association between the D allele of the ACE I/D polymorphism and AAAs in Europeans (OR = 1.338, 95% CI = 1.026-1.745, p = 0.031), but not in Asians (OR = 0.927, 95% CI = 0.660-1.303, p = 0.663). Furthermore, analysis using the recessive model, dominant model, and homozygote contrast all showed the same pattern for the D allele.

CONCLUSIONS

Our meta-analysis demonstrates that the ACE I/D polymorphism is associated with susceptibility to AAAs in European populations.

Common polymorphisms in the interleukin-22 gene are not associated with chronic plaque psoriasis

BACKGROUND

Psoriasis is a chronic inflammatory skin disease. Among other cytokines, interleukin 22 (IL-22) has been implicated in the pathogenesis of chronic plaque psoriasis. The purpose of this study was to investigate a hypothesized association between common IL-22 gene polymorphisms and chronic plaque psoriasis.

METHODS

Genotypes of 10 common polymorphisms of the IL-22 gene were determined by fluorogenic 5' exonuclease assays (TaqMan) in 475 patients with chronic plaque psoriasis and 252 controls.

RESULTS

Two blocks of high linkage disequilibrium, formed by eight polymorphisms upstream of exon 5 (rs2227485, rs2227491, rs2046068, rs1179251, rs1012356, rs2227501, rs2227503, rs976748) and two polymorphisms in the 3' near gene region (rs1182844, rs1179246), were observed within the IL-22 gene. Neither single polymorphisms nor haplotypes were significantly associated with the presence or clinical features of chronic plaque psoriasis (P > 0.05).

CONCLUSIONS

Our data suggest that the investigated IL-22 gene polymorphisms are unlikely major risk factors for chronic plaque psoriasis.