Anthoula Chatzikyriakidou

Endothelial function, but not carotid intima-media thickness, is affected early in menopause and is associated with severity of hot flushes.

CONTEXT The effect of early menopause on indices of vascular function has been little studied. OBJECTIVE The objective of the study was to investigate the effect of early menopause on indices of subclinical atherosclerosis and identify predictors of those indices in early menopausal women. DESIGN, SETTING, AND PARTICIPANTS This was a cross-sectional study that included 120 early menopausal women (age range 42-55 yr, <3 yr in menopause) recruited from the menopause outpatient clinic of an academic hospital and 24 age-matched premenopausal women. MAIN OUTCOME MEASURES Brachial artery flow-mediated dilation (FMD) and common carotid intima-media thickness (IMT) were studied. Estrogen receptor (ER)-alpha (rs2234693 T-->C and rs9340799 A-->G) and ERbeta (rs4986938 A-->G) polymorphisms were studied in menopausal women. RESULTS FMD was significantly lower in early menopausal women compared with controls (5.43 +/- 2.53 vs. 8.74 +/- 3.17%, P < 0.001), whereas IMT did not differ between groups (P > 0.8). Severity of hot flushes was the most important independent predictor for FMD (P < 0.001) in menopausal women. Women with moderate/severe/very severe hot flushes had impaired FMD in contrast to women with no/mild hot flushes or controls. Women with no/mild hot flushes did not differ compared with controls. Age and systolic blood pressure were the main determinants of IMT (both P = 0.004). ER polymorphisms were not associated with vascular parameters. CONCLUSIONS Impairment of endothelial function is present in the early menopausal years, whereas carotid IMT is not affected. Severity of hot flushes is the main determinant of endothelial dysfunction in early menopausal women. The studied ER polymorphisms do not offer important information on vascular health in early menopause.

The role of microRNA-146a (miR-146a) and its target IL-1R-associated kinase (IRAK1) in psoriatic arthritis susceptibility.

MicroRNAs have shown different expression patterns in immune diseases. The present study explores the association of miRNA‐146a variant rs2910164 and of two IRAK1 (target of miR‐146a) polymorphisms rs3027898 and rs1059703 with psoriasic arthritis (PsA). Twenty‐nine PsA and 66 controls were enrolled in the study. To study if the statistical significant differences between patients with PsA and controls are independent to psoriasis, we expanded the study in 49 patients with ankylosing spondylitis (AS). Strong statistical significant difference was observed in IRAK1 rs3027898 polymorphism distribution between patients with PsA and controls (P = 0.003), as between patients with AS and controls (P < 0.001). Marginally significant difference was observed in distribution of IRAK1 rs1059703 genotypes between patients with PsA and controls (P = 0.058), but no difference was observed in miRNA‐146a rs2910164 distribution (P = 0.394). This is the first study that addresses IRAK1 rs3027898 polymorphism association with PsA susceptibility, but further studies could help to understand the extent of the proposed association.

Transcription regulatory polymorphism −43T>C in the 5′-flanking region of SLC19A1 gene could affect rheumatoid arthritis patient response to methotrexate therapy

The reduced folate carrier (RFC) protein (SLC19A1-gene) has central role in the uptake and intracellular accumulation of folates. In this respect, we investigate whether SLC19A1 genetic variations could affect rheumatoid arthritis (RA) patient response to antifolate treatment. One hundred six unrelated RA patients were enrolled in this study. Polymerase chain reaction (PCR)-single strand conformation polymorphism (SSCP) was used as the screening method for genetic variants. Unusual SSCP patterns were characterized by direct sequencing of the PCR products and subsequently restriction assays were established. Western blot analysis of RFC protein was performed in respect of the identified SLC19A1 genotypes. Patient response to methotrexate (MTX) was evaluated using disease activity for 28 joint indices score, American College of Rheumatology 20% and 50% scores. No mutation was found in the SLC19A1 gene, but three polymorphic variants: the −43T>C in the 5′-flanking sequence to the ATG-transcription start site; and the 80G>A (R27H) and 696C>T (P232P) in the coding gene sequence. The wild type alleles of the three polymorphisms were in strict linkage disequilibrium. Western blot analysis revealed that the non-wild type allele of polymorphism −43T>C is associated with low RFC protein expression levels. Furthermore, the genotypic analysis of the functional polymorphic variant −43T>C revealed to be insufficient to predict patient response to MTX therapy. According to recent literature, several transport systems account for folate membrane transport. Additionally, in previous studies discrepancies have been reported to exist between the same genetic variants and their use in prediction of patient response to MTX therapy. Therefore, the present genotypic–phenotypic association study of a functional polymorphism revealed the need of a complex genotypic analysis in order to predict patient response to folate antagonists’ therapy.

Evidence for association of SLC7A9 gene haplotypes with cystinuria manifestation in SLC7A9 mutation carriers

Cystinuria is a complex genetic disorder. In the present study, we report on the strict linkage disequilibrium of SLC7A9 mutations with the wild type SLC7A9 haplotype of 15 single nucleotide polymorphisms (SNPs) and their effect on cystinuria manifestation and classification. Specifically, screening for mutations and polymorphisms was performed in the family members of ten cystinuric patients with SLC7A9 gene mutations. The molecular genetic and clinical data of cystinuric patients and their relatives were combined to construct the SLC7A9 SNP haplotypes and evaluate the manifestation of the disorder in carriers for a SLC7A9 gene mutation. It was found that all carriers of a SLC7A9 mutation manifested cystinuria if their normal allele had non-wild type nucleotides in two or more of the identified polymorphic sites. Subsequently, the polymorphic background of the SLC7A9 gene probably affects the expression of the disorder in SLC7A9 mutation carriers and points to a revised genetic classification of cystinuric patients.

Absence of SLC22A12 gene mutations in Greek Caucasian patients with primary renal hypouricaemia

Objective. Primary renal hypouricaemia is a hereditary clinical disorder characterized by increased renal urate clearance due to isolated renal tubular defect of uric acid transport. There have been only a few studies on primary renal hypouricaemia in Caucasian populations. Defects in the SLC22A12 gene, which encodes the renal urate transporter URAT1, have been reported to be related to the disease pathogenesis. This study was undertaken to elucidate whether SLC22A12 gene mutations are responsible for low serum uric acid levels in Greek people. Material and methods. Nine Greek Caucasian subjects with primary renal hypouricaemia were included in the study. All had serum uric acid less than 2.5 mg dL−1 (0.14 mmol L−1), fractional excretion of uric acid more than 10 % and no other known causes of hypouricaemia. Mutation analysis of the SLC22A12 gene was performed. Results. No mutation was found – only the previously reported silent polymorphism 1246T>C (His142His) in exon 2 of the SLC22A12 gene. Conclusions. No previously reported mutation of URAT1 was associated with primary renal hypouricaemia in Greek subjects.

Genetics in rheumatoid arthritis beyond HLA genes: What meta-analyses have shown?

OBJECTIVE Rheumatoid arthritis (RA) is a complex disorder with many genetic and environmental factors to account for disease susceptibility. Individual genetic association studies usually suffer from small sample size leading to biased results of polymorphisms association with RA liability. Therefore, meta-analyses seem to resolve this limitation, up to a point, increasing the power of statistical analyses. In this review, we summarize the current knowledge of non-HLA genetic factors contributing to RA predisposition based on meta-analyses. METHODS Using the key words: rheumatoid arthritis, meta-analysis, and polymorphism, we searched the PubMed database for the associated articles. Up to the middle of November 2012, seventy-nine articles fulfilled the criteria and highlighted the current findings on the genetic factors contributing to RA susceptibility. RESULTS The association with RA was confirmed for 32 gene polymorphisms, being population specific in some cases. However, meta-analyses did not confirm an association in case of 16 gene variants, previously studied in individual studies for their association with RA. CONCLUSIONS The use of bioinformatics tools and functional studies of the summarized implicated genes in RA pathogenesis could shed light on the molecular pathways related to the disorder, helping to the development of new drug targets for a better treatment of RA.

Ethnicity‐Based Differences in the Association of LOXL1 Polymorphisms with Pseudoexfoliation/Pseudoexfoliative Glaucoma: A Meta‐Analysis

Pseudoexfoliation (PEX) is an age‐related disorder of the extracellular matrix; it is strongly associated with glaucoma, the leading cause of irreversible blindness worldwide. We conducted an ethnic‐based meta‐analysis of the association of LOXL1 polymorphisms with PEX/pseudoexfoliative glaucoma (PEXG). Association studies were retrieved systematically from PubMed, EMBASE, and Web of Knowledge. Allelic and genotype frequencies of rs3825942, rs1048661, and rs2165241 were compared between PEX/PEXG and controls. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using a random effects model. Overall, 39 independent cohorts were included. Rs3825942 (G) was an at risk allele for PEX/PEXG in Caucasians, Japanese, Koreans, Chinese, South Asians, and Middle Easterners, but protective in Black South Africans (OR = 0.10, 95%CI:0.06–0.16). Rs1048661 (G) was an at risk allele for PEX/PEXG in Caucasians, South Asians, Middle Easterners and Black South Africans, but was protective in Japanese (OR = 0.03, 95%CI:0.02–0.06) and Koreans (OR = 0.10, 95%CI:0.05–0.22). These associations we‐re confirmed for the genotypic recessive models. Rs2165241 (C) was a protective allele for PEX/PEXG in Caucasians, but was an at risk allele in Japanese (OR = 7.49, 95%CI:3.22–17.41) and Koreans (OR = 6.63, 95%CI:2.60–16.90). This was confirmed for the genotypic dominant model. Other genetic and/or environmental factors may modify the effect of LOXL1 polymorphisms in certain ethnic groups.

Altered sequence of the ETS1 transcription factor may predispose to rheumatoid arthritis susceptibility

Objective: ETS1 belongs to the ETS family of transcription factors that regulate the expression of various immune-related genes. The aim of this study was to identify whether the ETS1 single nucleotide polymorphism (SNP) rs11221332, described in Caucasian subjects, plays a role in rheumatoid arthritis (RA) susceptibility. Methods: We genotyped this polymorphism in 136 unrelated patients with RA and 147 healthy individuals with no history of autoimmune disease. Genotyping was performed with a polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) assay and the data were analysed using SPSS statistical software. Results: A statistically significant difference was observed in the distribution of the rs11221332 genotypes between RA patients and controls (p = 0.041). Comparing the distribution of rs11221332 alleles between the groups studied, a greater difference was found [odds ratio (OR) 1.504, 95% confidence interval (CI) 1.036–2.183; p = 0.039]. Conclusions: The present study revealed, for first time, the positive association of a polymorphism in the sequence of the ETS1 transcription factor with RA susceptibility. Further studies in other ethnic groups of patients are needed to confirm the results of the present genetic association study related to ETS1, a widely used transcription factor in the regulation of the expression of various genes.

The (TTTA)n polymorphism of aromatase (CYP19) gene is associated with age at menarche

BACKGROUND Twin studies have shown that age at menarche may be subject to hereditary influences but the specific determinants are unknown. Estrogens are known to have an important role in menarche. Since the enzyme aromatase is responsible for the conversion of androgens to estrogens, the aromatase (CYP19) gene could be a candidate gene for the regulation of menarche. The aim of this study was to investigate the possible association of the CYP19(TTTA)(n) polymorphism with age at menarche. METHODS We studied 130 healthy adolescent females from a closed community in North-Western Greece. Information on menarche was obtained through interviews. The BMI was recorded. The CYP19(TTTA)(n) polymorphism was genotyped. RESULTS The mean age at menarche was 12.9 ± 1.2 years and the BMI = 19.8 ± 2.3 kg/m(2). Genotype analysis revealed 5 CYP19(TTTA)(n) alleles containing 7-11 TTTA repeats. Girls homozygous for the allele with 7 TTTA repeats had earlier menarche (12.45 ± 0.9 years) than girls carrying other genotypes (13.0 ± 1.2 years, P = 0.025), whereas the BMI was not different between these two subgroups. Carriers of the allele with 11 TTTA repeats had later menarche compared with non-carriers (14.1 ± 0.75 versus 12.8 ± 1.2 years, P< 0.001), whereas no difference was found in BMI values. Comparing girls with early menarche (<12 years, 25th percentile) with girls with late menarche (>13.75 years, 75th percentile), we found that 31% of the girls with early menarche were homozygous for the (TTTA)(7) allele compared with 6.9% among girls with late menarche (P = 0.018). In addition, none of the girls carrying the (TTTA)(11) allele was found among the subgroup with early menarche, whereas 24.1% of girls with late menarche had the (TTTA)(11) allele (P = 0.001). No association between other alleles and age at menarche was found. CONCLUSIONS There is evidence for a genetic contribution of the CYP19 gene to the age at menarche.

Glucocorticoid receptor variants may predispose to rheumatoid arthritis susceptibility

Objectives: Deregulation of glucocorticoid (GC) secretion could be associated with rheumatoid arthritis (RA). The GC receptor (GR) has two isoforms. In the present study, we explored the role of GR‐α polymorphisms rs33388, rs33389, and Bcl I, and the GR‐β variant rs6198 in RA susceptibility. Methods: One hundred and thirty‐six RA patients and 148 ethnic matching controls were studied. Polymorphisms rs33388 and Bcl I were genotyped by polymerase chain reaction restriction fragment length polymorphism (PCR‐RFLP), and variants rs33389 and rs6198 by polymerase chain reaction single‐strand conformation polymorphism (PCR‐SSCP) coupled with sequencing. Arlequin and SPSS softwares were used in the statistical analysis. Results: The polymorphisms studied were in Hardy–Weinberg equilibrium in both groups. A marginally statistical significant difference was observed in the distribution of rs33388 genotypes between RA patients and controls (p = 0.053). When the A and T alleles were compared, the statistical significance was p = 0.025. Specific complex genotypes were also differentially distributed: the GR‐α complex genotypes (a) [homozygote (homo) wild‐type (wt) rs33388–homo wt rs33389] (11% RA vs. 21% controls; p = 0.023), (b) [homo wt rs33388–homo wt rs33389–homo non‐wt Bcl I] (0.7% RA vs. 4.7% controls; p = 0.042), and (c) the GR‐β complex genotype [homo wt rs33388–homo wt rs33389–homo non‐wt Bcl I–homo wt rs6198] (0.7% RA vs. 4.7% controls; p = 0.042). Conclusions: GR‐α and GR‐β polymorphisms are potentially associated with RA susceptibility. However, additional studies in larger and other ethnic groups of patients are needed to confirm the results of the present study.