Polymorphism of the interleukin-4, interleukin-13, and signal transducer and activator of transcription 6 genes in Indonesian children with minimal change nephrotic syndrome

BACKGROUND/AIMS: Minimal change nephrotic syndrome (MCNS) in children is frequently associated with allergy and immunoglobulin E (IgE) production. T-helper subtype 2 cytokines, such as interleukin (IL)-4 and IL-13, have been implicated in the regulation of IgE production. We investigated the associations of gene polymorphisms of IL-4, IL-13, and signal transducer and activator 6 (STAT6) in Indonesian children with MCNS (n = 84) and controls with neither allergic nor renal disease (n = 61). METHODS: Polymerase chain reaction-restriction fragment length polymorphism was used to determine the IL-4 promoter gene polymorphism (-590C/T) and IL-13 gene polymorphism (4257G/A), and direct sequencing was used for the STAT6 3S untranslated region (2964G/A) polymorphism. RESULTS: There was a significant difference between the MCNS group and the controls in the genotypic distribution of IL-4 and IL-13 gene polymorphism. In the case of the IL-4 promoter gene, the frequency of the CC homozygote was significantly lower in the MCNS group than in the controls, while, in the case of IL-13, the frequency of the GG homozygote was significantly lower in the MCNS group. However, there was no difference between the MCNS group and the controls in the STAT6 gene polymorphism. CONCLUSION: The genetic variations in the IL-4 and IL-13 genes may be associated with predisposition to MCNS.     

Interleukin-10 production genotype protects against acute persistent rejection after lung transplantation.

BACKGROUND: Our previous studies demonstrated that cytokine gene polymorphisms are related to acute rejection in pediatric heart transplantation; a decreased tumor necrosis factor (TNF)-alpha production genotype combined with an increased or intermediate interleukin (IL)-10 production genotype was associated with the smallest incidence of acute rejection. The objective of this study was to determine whether cytokine genotypes TNF-alpha, IL-10, IL-6, interferon-gamma, and transforming growth factor beta were associated with acute persistent rejection after lung transplantation. METHODS: Cytokine genotyping was performed in 119 adult lung transplantation recipients who underwent surveillance transbronchial biopsies during their first year after transplantation. We categorized recipients with acute persistent rejection if they had 2 consecutive biopsy specimens at >/=Grade A2 despite anti-rejection treatment. We performed cytokine genotyping using the polymerase chain reaction-sequence specific primers technique, with a commercially available kit. RESULTS: We analyzed the IL-10 genotype in 116 patients. For the increased IL-10 production genotype, 7 of 20 patients (35%) were persistent rejecters. In comparison, 57 of 96 patients (59%) with intermediate or decreased IL-10 production genotype had acute persistent rejection (p = 0.046). For IL-10 haplotypes associated with intermediate IL-10 production, 30 of 45 patients with GCC/ACC haplotype (67%) had acute persistent rejection compared with 10 of 22 patients with GCC/ATA (45%). In the patients with intermediate IL-10 production, 17 of 22 (77%) with IL-10 GCC/ACC and IL-6 G/C had acute persistent rejection, whereas only 2 of 7 patients (29%) with IL-10 GCC/ATA and IL-6 G/G had acute persistent rejection (p = 0.018). CONCLUSIONS: In lung transplant recipients, the increased IL-10 production genotype protects against acute persistent rejection when compared with the intermediate or decreased IL-10 production genotypes. The intermediate IL-10 production genotype in lung transplant recipients can be differentiated into 2 haplotype responses, with the GCC/ACC haplotype associated more with acute persistent rejection. In lung transplant recipients, the immunomodulatory effects of IL-6 are differentiated in the G/C and G/G alleles in conjunction with IL-10 haplotypes, with G/C being associated with more acute persistent rejection in conjunction with the IL-10 GCC/ACC haplotype. Future pharmacogenomic models may incorporate these associations with acute persistent rejection in lung transplant recipients to formulate individualized therapeutic regimens.     

白介素-18基因多态性与结直肠癌易感性的关系

目的探讨白介素-18（m-18）基因单核苷酸多态性及其单倍型与结直肠癌易感性之间的关系。方法以170例结直肠癌患者和160名健康对照者为研究对象,应用聚合酶链反应一限制性片段长度多态性（PCR-RFLP）的方法对IL．18基因-137G／C、-607C／A单核苷酸多态性进行基因分型,同时用SHEsis软件分析IL-18基因的连锁不平衡及单倍型频率。结果IL-18基因-607C／A多态性在结直肠癌患者和健康人群中的分布差异无统计学意义（P〉0．05）．而IL-18基因-137G／C多态性在两组人群中的分布差异有统计学意义（P〈0．05）。等位基因频率的相对风险分析显示．C等位基因携带者患结直肠癌的风险是G等位基因的1．814倍（OR=1．814,95％CI：1．246～2．642）。联合基因型分析显示,IL-18基因-137G／C、-607C／A单核苷酸多态性存在着强烈的连锁不平衡（ID＇｜=0．945）,-137C／-607A单倍型频率在结直肠癌患者中显著高于健康人群（P〈0．05）。-137C／-607A单倍型携带者显著增加了结直肠癌的发病风险（OR=1．637,95％CI：1．100～2．437）。结论IL—18基因-137G／C多态性和-137C／-607A单倍型与结直肠癌的发病具有相关性．其中-137C等位基因可能是结直肠癌的遗传易感基因。     

T-cell subsets,interleukin-2 receptor expression and production of interleukin-2 in minimal change nephrotic syndrome

This study was designed to investigate T-lymphocyte subsets interleukin-2 receptor (IL-2R) expression and IL-2 production in minimal change nephrotic syndrome (MCNS). Peripheral blood T-lymphocytes and IL-2R expression were analysed using fluorescein isothiocyanatelabelled CD3, CD4, CD8 and CD25 monoclonal antibodies with flow cytometry. IL-2 production was determined by enzyme immunoassay. Ten children with MCNS in relapse and in remission were evaluated. Thirteen healthy children served as controls. The patients in relapse demonstrated a moderate decrease in the total absolute lymphocyte counts and CD8(+) T-lymphocytes compared with controls (P<0.05) and had a greatly increased IL-2R expression in frashly isolated, unstimulated peripheral lymphocytes compared with patients in remission and controls. While this was not statistically significant, IL-2R expression on cultured lymphocytes stimulated with phytohaemagglutinin was significantly elevated in relapse compared with those in remission and controls (P<0.05). IL-2 production did not correlate well with IL-2R expression and there was no significant difference between the groups. Our results suggest that T-cell subset changes and high IL-2R expression on peripheral lymphocytes may indicate the presence of stimulated T-cell populations in MCNS which could contribute to the immunopathogenesis.     

Association of an IL-1A 3'UTR polymorphism with end-stage renal disease and IL-1 alpha expression

BACKGROUND: We evaluated polymorphisms in the interleukin-1 alpha 3'-untranslated region (IL-1A 3'[UTR]) for association with type 2 diabetes-associated (DM) and nondiabetic-associated (non-DM) end-stage renal disease (ESRD) in two ethnic groups. METHODS: IL-1A 3'UTR polymorphisms were identified by alignment of overlapping human expressed sequence tags (ESTs). Sequence ambiguities were experimentally confirmed and variants genotyped to test for association with ESRD in 75 unrelated Caucasians with DM ESRD, 95 unrelated Caucasian controls and, in a parallel study, 92 unrelated African Americans with type 2 DM ESRD, 95 unrelated African Americans with non-DM ESRD, and 86 unrelated African American controls. IL-1A 3' UTR genotype and lipopolysaccharide (LPS)-stimulated IL-1 alpha protein levels were measured in healthy Caucasians (N = 112) and African Americans (N = 101) to evaluate association between genotype and protein level. RESULTS: A polymorphism in the 3' UTR of the human IL-1A gene was associated with ESRD and IL-1 alpha protein expression. The polymorphism consists of two single nucleotide polymorphisms (SNPs) and an insertion/deletion generating four different haplotypes: TN7TTCAA, AN7TTCAA, TN7TTCAG and an allele deleted for four internal bases, TN7(delTTCA)A. The 4 bp deletion allele, TN7(delTTCA)A, was significantly less common among Caucasian DM ESRD and African American non-DM ESRD patients (recessive model; P = 0.0364 and P = 0.0293, respectively). In vitro, this polymorphism is associated with the amount of IL-1 alpha protein synthesized in LPS-stimulated lymphocytes from healthy subjects (P = 0.0013, additive model), with the TN7(delTTCA)A haplotype associated with higher levels of stimulated IL-1 alpha. CONCLUSION: The association of the TN7(delTTCA)A haplotype with higher levels of IL-1 alpha expression and reduced risk for ESRD is consistent with involvement of cytokines in risk for developing nephropathy.     

Variants of C1GALT1 gene are associated with the genetic susceptibility to IgA nephropathy

IgA nephropathy (IgAN) is a polygenic disorder and the precise role of genetic factors remains elusive. Increasing evidences have implicated the aberrant galactosylation of IgA1 molecules in the pathogenesis of IgAN. The galactosyltransferase, core 1 beta3-Gal-T, and its chaperone, Cosmc, play important roles in beta1,3 glycosylation of IgA1 molecule. A case-control association study was performed to investigate the association between single-nucleotide polymorphisms (SNPs) of C1GALT1 and C1GALT1C1 genes and the susceptibility to IgAN. A total of 1164 subjects were enrolled, including 670 IgAN patients and 494 geographically matched healthy controls. Five SNPs, -734C/T, -465A/G, -330G/T, -292C/-, and 1365G/A in C1GALT1 were selected as tagging SNPs. The D allele and DD genotype of -292C/- in IgAN patients were significantly lower than in the controls (P<0.01). The frequency of haplotype YATIG (Y=C or T) was significantly lower in patients than in controls (0.0719 vs 0.1168, P=2.775 x 10(-4), odds ratio (OR)=0.70). The haplotype YAGDA (0.1236 vs 0.0791, P=3.815 x 10(-3), OR=1.77) and YATDG (0.0840 vs 0.0298, P=1.258 x 10(-5), OR=3.03) were significantly higher in patients than in controls. The present study suggested that the polymorphisms of C1GALT1 gene were associated with the genetic susceptibility to IgAN in Chinese population.     

Influence of cytokine gene polymorphisms on graft rejection in Turkish patients with renal transplants from living related donors

Introduction

Certain cytokine gene polymorphisms (CGPs) have been shown to be associated with renal transplant rejection or graft outcomes. We sought to evaluate the relationship between gene polymorphisms in patients with acute rejection episodes (rejection group, RG, n = 19) versus those with stable graft function (nonrejection group, NRG, n = 71) in comparison with healthy control subjects (HCG, n = 150). The follow-up time period was 18 months. In the present study, 22 single nucleotide polymorphisms distributed across 13 cytokine and cytokine receptor genes were genotyped by polymerase chain reaction sequence-specific primers (PCR-SSP) using the Heidelberg kit.

Results

The interleukin-2 (IL-2) TT/GT haplotype was observed among 36.8% of patients in the RG and 6.7% of those in the HCG but not in any NRG patient (P < .0001; .0007). The IL-2 GG/TT haplotype was observed among 13 NRG and 9 HCG patients (P = .007). The IL-2 GG/GG haplotype was noted in 18.7% of HCG and 4.2% of NRG patients (P = .0033) and the IL-2 TT/TT haplotype in 5 and 8 patients of NRG and HCG, respectively, but not in any RG patient (P > .05). The transforming growth factor beta1 CG/CC haplotype was noted in 15 NRG (21.1%) and 4 HCG patients but not any RG (P < .0001). The IL-2 + 166 GT genotype was detected in 36.8% of RG, 8.5% of NRG, and 14.7% of HCG patients (P = .005, .0244). The IL-2 −330 GG genotype was demonstrated in 32 healthy controls and 3 nonrejection transplant patients (P = .0007). Significant differences were found between NRG and HCG for IL-6 565 AG, IL-1 beta −511 TT and +3962 CC/CT/TT genotypes.

Discussion

We observed significant differences among the frequencies of IL-2 gene polymorphisms between the RG and the NRG, which were consistent with previous clinical but not in vitro studies.     

Influence of cytokine gene polymorphisms on graft rejection in Turkish patients with renal transplants from living related donors

Background

Certain cytokine gene polymorphisms (CGPs) have been shown to be associated with renal transplant rejection episodes or graft outcomes. We sought to evaluate the relationships between gene polymorphisms and acute rejection episodes (RG, n = 19) versus stable graft function (NRG, n = 71) in transplant recipients compared with healthy control subjects (HCG, n = 150). The follow-up time period was 18 months. Using polymerase chain reaction sequence-specific primers with the Heidelberg kit we genotyped 22 single nucleotide polymorphisms distributed across 13 cytokine and cytokine receptor genes.

Results

Interleukin (IL)-2 TT/GT haplotype was found in 36.8% of RG patients and 6.7% of HCG but not among the NRG (P < .0001; .0007). The IL-2 GG/TT haplotype was observed among 13 NRG and nine HCG patients (P = .007); the IL-2 GG/GG haplotype, 18.7% HCG and 4.2% NRG patients (P = .0033); and the IL-2 TT/TT haplotype, five NRG and eight HCG patients, but none of the RG cohort (P > .05). The transforming-growth factor-beta 1 CG/CC haplotype was noted in 15 NRG (21.1%) and four HCG but no RG patients (P < .0001). The IL-2 +166 GT genotype was detected in 36.8% of RG, 8.5% of NRG, and 14.7% of HCG patients (P = .005, .0244). The IL-2 −330 GG genotype was demonstrated in 32 healthy controls and three nonrejection transplant patients (P = .0007). Significant differences were concluded between NRG and HCG for IL-6 565 AG, IL-1beta −511 TT and +3962 CC/CT/TT genotypes.

Discussion

We observed significant differences among the frequencies of IL-2 gene polymorphisms among RG and NRG subjects, which agreed with previous clinical, but not in vitro studies.     

Adrenomedullin and nitrite levels in children with minimal change nephrotic syndrome

Nitric oxide (NO) serves many functions within the kidney, and recent evidence suggests that NO contributes to glomerular injury. Adrenomedullin (AM) is a novel hypotensive peptide originally isolated from human pheochromocytoma. Recent studies showed that plasma AM concentrations correlated with the extent of proteinuria. We have examined the possible role of these two agents by studying plasma and urinary total nitrite (NO⁻ ₂ + NO⁻ ₃) and AM levels in children with minimal change nephrotic syndrome (MCNS). In comparison with healthy controls, children with MCNS had increased urinary nitrite excretion (μmol/mg urinary creatinine), irrespective of whether the disease was in relapse or remission (3.2±0.2 in relapse, n=13; 1.9±0.3 in remission, n=12; 1.0±0.2 in controls, n=10, P<0.05). Plasma nitrite levels (μmol/l) were high in relapse compared with controls (53.2±8.7 vs. 32±4.0, P<0.05). Plasma AM levels (pmol/ml) were decreased in relapse (27.6±1.4 in relapse, 43.3±1.2 in remission, 41.5±1.6 in controls, P<0.05). Urinary AM levels (pmol/mg urinary creatinine) were significantly higher in relapse than in remission and in controls (156±43 in relapse, 56±18 in remission, 36±16 in controls, P<0.05). Our data indicate that NO may play a role in mediating the clinical manifestations of MCNS in children. However, changes in AM levels may be the result of heavy proteinuria. Received: 20 December 1999 / Revised: 12 June 2000 / Accepted: 15 June 2000     

Susceptibility to Paget's disease of bone is influenced by a common polymorphic variant of osteoprotegerin.

To clarify the role of the TNFRSF11B gene encoding osteoprotegerin (OPG), in Paget's disease of bone (PDB) we studied TNFRSF11B polymorphisms in an association study of 690 UK subjects and in a worldwide familial study of 66 kindreds. We found that the G1181 allele of TNFRSF11B, encoding lysine at codon 3 of the OPG protein, predisposes to both sporadic and familial PDB. INTRODUCTION: Paget's disease of bone (PDB) is a common disorder characterized by focal abnormalities of bone turnover. Genetic factors are important in the pathogenesis of PDB, and studies have shown that inactivating mutations of the TNFRSF11B gene, encoding osteoprotegerin (OPG), cause the rare syndrome of juvenile Paget's disease. In this study, we sought to determine whether polymorphisms of the TNFRSF11B gene contribute to the pathogenesis of classical PDB. MATERIALS AND METHODS: We screened for polymorphisms of the TNFRSF11B gene by DNA sequencing of the proximal promoter, coding exons, and intron-exon boundaries in 20 PDB patients and 10 controls. Informative single nucleotide polymorphisms (SNPs), including a G1181C SNP, which predicts a lysine-asparagine substitution at codon 3 of the OPG signal peptide and haplotypes, were related to the presence of PDB in 312 cases compared with 378 controls and to transmission of PDB in 140 affected offspring from 66 kindreds with familial PDB. RESULTS AND CONCLUSIONS: The G1181 allele was significantly over-represented in PDB patients (chi(2) = 5.7, df = 1, p = 0.017, adjusted alpha = 0.024), equivalent to an odds ratio for PDB of 1.55 (95% CI: 1.11-2.16). The distribution of TNFRSF11B haplotypes significantly differed in sporadic PDB cases and controls (chi(2) = 30.2, df = 9, p < 0.001) because of over-representation of haplotypes containing the G1181 allele in cases. The family study showed that the most common haplotype containing the G1181 allele was transmitted more frequently than expected to 140 individuals with familial PDB (chi(2) = 7.35, df = 1, p < 0.01), and the transmission disequilibrium was even more pronounced in a subgroup of 78 familial PDB patients who did not carry mutations of the SQSTM1 gene (chi(2) = 8.44, df = 1, p < 0.005). We conclude that the G1181 allele of TNFRSF11B, encoding lysine at codon 3 of the OPG protein, predisposes to the development of sporadic PDB and familial PDB that is not caused by SQSTM1 mutations.     

HLA alleles in frequently relapsing steroid-dependent and -resistant nephrotic syndrome in Egyptian children

The association between HLA class II antigens and childhood primary nephrotic syndrome has been reported in different populations. To investigate this association in Egyptian children, DRB1 alleles were typed by DNA polymerase chain reverse hybridization in 20 frequent relapsers/steroid-dependent and 14 steroid-resistant children with minimal change nephrotic syndrome (MCNS) and 121 unrelated healthy controls from the northern part of Egypt. The strength of the association was expressed as the relative risk (RR) estimated by the odds ratio. The DRBI *07011 allele frequency was significantly higher among patients than controls (78.9% vs. 16%, Pc <0.001). The etiological fraction (EF) was high at 0.75 [RR=20.1, confidence interval (CI)=6.0–66.7]. Similarly, patients with steroid-resistant MCNS had a higher frequency of the DRBI *07011 allele than controls (64.3% vs. 16.5%, P c<0.001). The EF was high at 0.57 (RR=9.6, CI 2.9–31.7). In the whole group of patients the frequency of DRBI *11 alleles was low compared with controls (11.4% vs. 32.2%, P =0.02), but was not significant when P was corrected. In conclusion, the DRBI *07011 allele confers susceptibility to a frequently relapsing and steroid-dependent or steroid-resistant course of childhood MCNS. These patterns of the disease seem to have the same immunogenetic components.     

Mycophenolate mofetil-based immunosuppression and cytokine genotypes: effects on monokine secretion and antigen presentation in long-term renal transplant recipients

BACKGROUND: It has been suggested that increased monocyte responses might play a role in chronic allograft rejection. METHODS: We investigated in vitro monokine responses in 112 patients with long-term stable kidney graft function (ST patients; n=80, non-mycophenolate mofetil [MMF]; n=32, MMF) and 25 patients with chronic renal transplant rejection (CR patients; non-MMF). Interleukin 10 and tumor necrosis factor (TNF)-alpha promoter gene polymorphisms were tested by polymerase chain reaction and sequence-specific primers; antigen-presenting capacity (AC) of monocytes was tested by incubation with staphylococcal superantigens (SEA, SEE, SED). RESULTS: Although non-MMF-based immunosuppression in ST patients did not result in compromised AC or lipopolysaccharide (LPS)-stimulated monokine responses compared with healthy controls, we found MMF therapy to be associated with significantly reduced TNF-R1 expression on monocytes (P<0.001), suppressed AC (P<0.02, SED), and suppressed LPS-stimulated IL-1 beta, IL-10, and TNF-alpha secretion (P<0.01). Coinciding with a significantly higher steroid dosage in CR patients, IL-6 receptor and TNF-R1 expression on monocytes were down-regulated (P< or =0.02) and AC was suppressed in CR compared with ST (non-MMF) patients (P<0.01, SED; P<0.05, SEE). However, LPS-stimulated monokine secretion was not decreased or even enhanced (IL-6, granulocyte-macrophage colony-stimulating factor [GM-CSF]; P<0.05). Enhanced in vitro IL-10 responses (>500 pg/mL) were found predominantly in non-MMF-treated patients with the IL-10 genotype GCC (GCC: 23/62 [37%], non-GCC: 2/27 [7%], P<0.005; GCC and non-MMF: 22/47 [47%], GCC and MMF: 1/15 [7%], P<0.005]. CONCLUSION: Steroids and azathioprine did not sufficiently suppress monokine responses, whereas MMF treatment might inhibit chronic graft rejection because of suppression of TNF-R1 expression and vigorous inhibition of monokine secretion. MMF treatment may especially be indicated in patients with the IL-10 "high-producer" genotype GCC.     

Lack of Association of the APOL1 G3 Haplotype in African Americans with ESRD

Apolipoprotein L1 gene (APOL1) G1 and G2 variants are strongly associated with progressive nondiabetic nephropathy in populations with recent African ancestry. Selection for these variants occurred as a result of protection from human African trypanosomiasis (HAT). Resequencing of this region in 10 genetically and geographically distinct African populations residing in HAT endemic regions identified eight single nucleotide polymorphisms (SNPs) in strong linkage disequilibrium and comprising a novel G3 haplotype. To determine whether the APOL1 G3 haplotype was associated with nephropathy, G1, G2, and G3 SNPs and 70 ancestry informative markers spanning the genome were genotyped in 937 African Americans with nondiabetic ESRD, 965 African Americans with type 2 diabetes–associated ESRD, and 1029 non-nephropathy controls. In analyses adjusting for age, sex, APOL1 G1/G2 risk (recessive), and global African ancestry, the G3 haplotype was not significantly associated with ESRD (P=0.05 for nondiabetic ESRD, P=0.57 for diabetes-associated ESRD, and P=0.27 for all-cause ESRD). We conclude that variation in APOL1 G3 makes a nominal, if any, contribution to ESRD in African Americans; G1 and G2 variants explain the vast majority of nondiabetic nephropathy susceptibility.     

TNFA2 and d2 alleles of the tumor necrosis factor alpha gene polymorphism are associated with onset/occurrence of idiopathic membranous nephropathy

Idiopathic membranous nephropathy (IMN) has a strong association with the major histocompatibility complex HLA B8DR3(17)DQ2 haplotype. The tumor necrosis factor (TNF)A gene is located within the major histocompatibility complex region on chromosome 6. We have studied the influence of two functional polymorphisms; the -308 (promoter region) and the TNFd microsatellites on initiation and/or progression of IMN. This was a case-control study comparing data from 100 Caucasians patients (67 male subjects; 67%) with IMN to 232 Caucasians local controls (171 male subjects; 74%). We have analyzed genotypes and alleles distributions and the role of these polymorphisms in disease progression towards end-stage renal failure or patient death. For -308 TNFA polymorphism, distribution of genotypes was significantly different between IMN and controls (chi(2)=16.25; P=0.0003): the A2 allele frequency was 28.0% in IMN vs 15.3% in controls (chi(2)=14.57; P=0.0001). For TNFd polymorphism, alleles distribution (from d1 to d7) was also significantly different between IMN and controls (chi(2)=56.74; P<0.0001) with both diminished d3 allele frequency (chi(2)=27.30; P<0.0001; Pc=0.001) and increased d2 allele frequency (chi(2)=29.95; P<0.0001; Pc=0.001) in IMN. We could not isolate any significant and independent influence of these different genotypes on IMN disease progression. The TNFA2 and TNFd2 alleles were strongly associated with occurrence/initiation of IMN and should be considered as susceptibility genes for this disease.     

COL1A1 haplotypes and hip fracture

Fragility fractures resulting from low‐trauma events such as a fall from standing height are associated with osteoporosis and are very common in older people, especially women. Three single nucleotide polymorphisms (SNPs) at the COL1A1 gene (rs1107946, rs11327935, and rs1800012) have been widely studied and previously associated with bone mineral density (BMD) and fracture. A rare haplotype (T‐delT‐T) of these three SNPs was found to be greatly overrepresented in fractured individuals compared with nonfractured controls, thus becoming a good candidate for predicting increased fracture risk. The aim of our study was to assess the association of this haplotype with fracture risk in Spanish individuals. We recruited two independent groups of ～100 patients with hip fracture (a total of 203 individuals) and compared the genotype and haplotype distributions of the three SNPs in the fractured patients with those of 397 control individuals from the BARCOS Spanish cohort. We found no association with risk of fracture at the genotype level for any of the SNPs, and no differences in the SNP frequencies between the two groups. At the haplotype level, we found no association between the T‐delT‐T haplotype and fracture. However, we observed a small but significant (p = 0.03) association with another rare haplotype, G‐insT‐T, which was slightly overrepresented in the patient group. © 2012 American Society for Bone and Mineral Research.     

Association of hypertension genotypes and decline in renal function after kidney transplantation

BACKGROUND: Polymorphisms of genes such as angiotensin-converting enzyme (ACE), angiotensinogen (AGT), and angiotensin receptor type I (AGTR1) have been associated with hypertension. Hypertension, in turn, has been associated with decreased renal allograft survival. Therefore, this study investigated whether single nucleotide polymorphisms (SNPs) in these genes are associated with decline in renal function posttransplantation. METHODS: We enrolled patients from a prospective cohort of renal transplant recipients of deceased donor kidneys being conducted at 9 centers in the Delaware Valley Region. Medical records were assessed every 6 months and estimated glomerular filtration rate (eGFR) was calculated using the Modification of Diet in Renal Disease equation. Genotypes of 10, 2, and 5 SNPs in the AGTR1, AGT, and ACE gene were analyzed, respectively. RESULTS: The G and the T alleles of the respective AGTR1 SNPs rs275704 and rs5182 were both associated with 50% decline in eGFR (HR for rs275704: CG=1.22, 95% confidence interval [CI] 0.67-2.25 and GG=2.55, 95% CI 1.22-5.32, overall P=0.03; HR for rs5182: CT=1.26, 95% CI 0.72-2.19 and TT=3.09, 95% CI 1.50-6.37, overall P=0.007) in the adjusted analysis. Similarly, haplotype analysis showed that AGTR1 SNPs were associated with 50% decline in eGFR (global P=0.010). The GG genotype of SNP rs275704 occurred more frequently in African Americans than in non-African Americans (44% vs. 7%, chi2=36.03, P<0.0001). In contrast, the TT genotype of SNP rs5182 occurred more frequently in non-African Americans than in African-Americans (24% vs. 2%, chi2=21.40, P<0.0001). Polymorphisms in the ACE and AGT genes were not associated with renal allograft outcomes. CONCLUSIONS: SNPs in AGTR1 gene are associated with decline in renal function posttransplantation.     

Single nucleotide polymorphisms in the proximal promoter region of the adiponectin (APM1) gene are associated with type 2 diabetes in Swedish caucasians

Adiponectin (APM1) is an adipocyte-derived peptide. The APM1 gene is located on chromosome 3q27 and linked to type 2 diabetes. In patients with type 2 diabetes, the adiponectin level in plasma is decreased in comparison to healthy subjects. To identify genetic defects of the APM1 gene that contribute to the development of type 2 diabetes, we genotyped 13 single nucleotide polymorphisms (SNPs) in 106 patients with type 2 diabetes, 325 patients with impaired glucose tolerance (IGT), and 497 nondiabetic control subjects in Swedish Caucasians by using dynamic allele-specific hybridization (DASH). We found that SNPs -11426(A/G) and -11377(G/C) in the proximal promoter region had significant differences of allele frequencies between type 2 diabetic patients and nondiabetic control subjects (P = 0.02 and P = 0.04, respectively). SNP-11426(A/G) was significantly associated with fasting plasma glucose in type 2 diabetic patients (P = 0.02) and in IGT subjects (P = 0.04), while the patients carrying CC and CG genotypes for SNP-11377(G/C) had a higher BMI than the patients with the GG genotype (P = 0.03). Haplotype analysis of 13 SNPs in the APM1 gene showed that estimates of haplotype frequencies in Swedish Caucasians are similar to those estimated in French Caucasians. However, no significant association of haplotypes with type 2 diabetes and IGT was detected in our study. The present study provides additional evidence that SNPs in the proximal promoter region of the APM1 gene contribute to the development of type 2 diabetes.     

Association of MEGSIN 2093C-2180T haplotype at the 3' untranslated region with disease severity and progression of IgA nephropathy.

BACKGROUND: MEGSIN is a gene predominantly expressed in the renal mesangium, and is upregulated in IgA nephropathy (IgAN). Our previous study has shown that the 2093C and 2180T alleles at the 3' untranslated region (3'UTR) of the gene are associated with susceptibility to IgAN, but the relationships of these genetic variants with the clinical manifestations and renal histological lesions of IgAN have not been examined previously. METHODS: 302 IgAN patients followed up for 52.8+/-22.5 months were investigated. Haplotypes at the 3'UTR were constructed using the 2093C/T and 2180C/T alleles. The genotype-phenotype relationship was studied by correlations of haplotypes and the clinical data and renal histopathological changes. RESULTS: The 2093C-2180T haplotype was present more often in patients with disease that progressed more rapidly (chi2((C-T/others)) = 8.429, P = 0.004), and was also correlated with hypertension (chi2((C-T/others)) = 6.459, P = 0.012), severe proteinuria (>or=2 g/d) (chi2((C-T/others)) = 6.332, P = 0.013), and Lee's class IV and V histological changes (chi2((C-T/others)) = 9.640, P = 0.008). CONCLUSION: In this Chinese population, the 2093C-2180T haplotype at the 3'UTR of MEGSIN gene is associated with more severe forms of IgAN, and more rapid disease progression. This provides further evidence for the involvement of genetic variations of MEGSIN in the pathogenesis of IgAN.