Interleukin 10 gene promoter polymorphisms in women with pregnancy loss: preferential association with embryonic wastage

Association between cytokine polymorphisms and recurrent pregnancy loss: A review of current evidence

Cytokines are a type of protein that play an important role in the immune response and can also affect many physiological processes in the body. Cytokine polymorphisms refer to genetic variations or mutations that occur within the genes that code for cytokines, which may affect the level of cytokine production and function. Some cytokine polymorphisms have been associated with an increased risk of developing certain diseases, while others may be protective or have no significant effect on health. In recent years, the role of cytokine polymorphisms in the development of recurrent pregnancy loss (RPL) has been studied. RPL or miscarriage is defined as the occurrence of two or more consecutive pregnancy losses before the 20th week of gestation. There are diverse causes leading to RPL, including genetic, anatomical, hormonal, and immunological factors. With regard to cytokine polymorphisms, a few of them have been found to be associated with an increased risk of RPL, for instance, variations in the genes that code for interleukin-6, tumor necrosis factor-alpha, and interleukin-10. The exact mechanisms by which cytokine polymorphisms affect the risk of recurrent miscarriage are still being studied, and further research is essential to fully understand this complex condition. This brief review aims to summarize the recent literature on the association between cytokine polymorphisms and RPL.

Association of IL-10-592 C > A /-1082 A > G and the TNFα -308 G > A with susceptibility to COVID-19 and clinical outcomes

BACKGROUND

Variation in host immune responses to SARS-CoV-2 is regulated by multiple genes involved in innate viral response and cytokine storm emergence like IL-10 and TNFa gene polymorphisms. We hypothesize that IL-10; -592 C > A and - 1082 A > G and TNFa-308 G > A are associated with the risk of SARS-COV2 infections and clinical outcome.

METHODS

Genotyping, laboratory and radiological investigations were done to 110 COVID-19 patients and 110 healthy subjects, in Ismailia, Egypt.

RESULTS

A significant association between the - 592 A allele, A containing genotypes under all models (p < 0.0001), and TNFa A allele with risk to infection was observed but not with the G allele of the - 1082. The - 592 /-1082 CG and the - 592 /-1082/ -308 CGG haplotypes showed higher odds in COVID-19 patients. Severe lung affection was negatively associated with - 592, while positive association was observed with - 1082. Higher D-dimer levels were strongly associated with the - 1082 GG genotype. Survival outcomes were strongly associated with the GA genotype of TNFa. -308 as well as AGG and AAA haplotypes.

CONCLUSION

IL-10 and TNFa polymorphisms should be considered for clinical and epidemiological evaluation of COVID-19 patients.

Impact of Interleukin-10 Promoter Region Polymorphisms on Recurrent Miscarriage: A Case-Control Approach

Background

Recurrent miscarriage (RM), defined as two or more consecutive miscarriages prior to the 20th week of gestation is characterised by multifactorial aetiology. The prevalence of RM varies from 0.8% to 13.5% amongst women of reproductive age. The aetiological basis of RM has been traced to chromosomal, anatomic, hormonal and immunologic factors while half of the cases remain idiopathic.

Aims

This study aimed to investigate the association of interleukin-10 (IL-10) polymorphisms with RM amongst the Indian population.

Settings and Design

The present study included a total of 414 individuals including RM women (n = 199) with two or more pregnancy losses and healthy women (n = 215) without any previous history of pregnancy loss were taken as the control group.

Materials and Methods

Demographic features and reproductive history of women with RM and healthy women were taken. Genotype analysis of IL-10 polymorphisms rs1800872 and rs1800896 was performed using the polymerase chain reaction (PCR) restriction fragment length polymorphism and amplification mutation refractory system PCR, respectively.

Statistical Analysis Used

Student's t-test was used to compare the demographic features and reproductive history amongst both groups. Pearson's Chi-square was used to calculate the Hardy-Weinberg equilibrium, allelic and genotypic frequencies. All the statistical analyses were performed using the SPSS (version 21, IBM SPSS, NY, USA).

Results

Our results suggested that the genotypic and allelic frequency of rs1800872 polymorphism did not differ significantly between RM cases and control women (P = 0.07 and P = 0.23, respectively). The GG genotype (P = 0.007) and G allele (P = 0.003) of rs1800896 were significantly associated with an increased risk of RM. A statistically significant difference was also found for the distribution of genetic models (dominant and co-dominant model) between both groups for rs1800896. However, haplotype analysis revealed that none of the haplotypes provides a risk for the progression of RM.

Conclusion

The study is the first of its kind from our region and provides baseline data on the genetics of RM.

Risk of Recurrent Pregnancy Loss in the Ukrainian Population Using a Combined Effect of Genetic Variants: A Case-Control Study

We assessed the predictive ability of a combined genetic variant panel for the risk of recurrent pregnancy loss (RPL) through a case-control study. Our study sample was from Ukraine and included 114 cases with idiopathic RPL and 106 controls without any pregnancy losses/complications and with at least one healthy child. We genotyped variants within 12 genetic loci reflecting the main biological pathways involved in pregnancy maintenance: blood coagulation (F2, F5, F7, GP1A), hormonal regulation (ESR1, ADRB2), endometrium and placental function (ENOS, ACE), folate metabolism (MTHFR) and inflammatory response (IL6, IL8, IL10). We showed that a genetic risk score (GRS) calculated from the 12 variants was associated with an increased risk of RPL (odds ratio 1.56, 95% CI: 1.21, 2.04, p = 8.7 × 10-4). The receiver operator characteristic (ROC) analysis resulted in an area under the curve (AUC) of 0.64 (95% CI: 0.57, 0.72), indicating an improved ability of the GRS to classify women with and without RPL. Ιmplementation of the GRS approach can help define women at higher risk of complex multifactorial conditions such as RPL. Future well-powered genome-wide association studies will help in dissecting biological pathways previously unknown for RPL and further improve the identification of women with RPL susceptibility.

Melatonin decreases and cytokines increase in women with placental insufficiency

Purpose: To investigate the levels of melatonin, proinflammatory and anti-inflammatory cytokines in pregnant women with placental insufficiency (PI).Materials and Methods: The PI was manifested as the intrauterine growth restriction syndrome of fetus (IUGR) in the third pregnancy trimester. The control group consisted of 20 women with uncomplicated pregnancy in the same term. The blood concentrations of melatonin, proinflammatory cytokines, such as tumor necrotizing factor-α (TNF-α), interleukin-1-β (IL-1-β), interleukin-6 (IL-6), and anti-inflammatory cytokines, such as interleukin-4 (IL-4), and interleukin-10 (IL-10), were studied.Results: The concentration of melatonin was found to decrease significantly if pregnancy was complicated by intrauterine fetal growth retardation (study group -126.87 ± 14.87 pg/ml, control group -231.25 ± 21.56 pg/ml, p < .001). The levels of proinflammatory cytokines in the study group were significantly higher as compared with the control group (TNF-α: study group -10.05 ± 1.35 pg/ml, control group -5.60 ± 1.50 pg/ml, p < .05; IL-1-β: study group -14.67 ± 2.13 pg/ml, control group -3.96 ± 0.92 pg/ml, p < .001; IL-6: study group -6.91 ± 0.99 pg/ml, control group -2.69 ± 0.99 pg/ml, p < .05). The same is true about anti-inflammatory cytokines (IL-4: study group -5.97 ± 0.50 pg/ml, control group -3.74 ± 0.62 pg/ml, p < .05; IL-10: study group -11.40 ± 1.50 pg/ml, control group -4.70 ± 3.20 pg/ml, p < .001). A moderate negative correlation between melatonin and IL-1-β in the group with PI (r = -0.3776, p = .0097), a closed negative correlation between the same indexes in the control group (r = -0.6785, p = .001), and a moderate negative correlation between melatonin and TNF-α (r = -0.4908, p = .02) were found.Conclusions: The blood level of melatonin significantly decreases in case of placental insufficiency, manifested as intrauterine fetal growth restriction. Strengthening of the proinflammatory immunity shown as the increasing of the levels of TNF-α, IL-1-β, and IL-6 levels is also present in case of IUGR. Increase of the serum concentration of the anti-inflammatory cytokines, such as IL-4 and IL-10, in our opinion, can be explained by activation of compensatory mechanisms, which decrease the risk of premature labor.

Cytokines Interleukin 4 (IL-4) and Interleukin 10 (IL-10) Gene Polymorphisms as Potential Host Susceptibility Factors in Virus-Induced Encephalitis

Background

This study aimed to analyze and explore the relationship between the cytokines IL-4 and IL-10 in relation to gene polymorphism and their respective effects on the susceptibility to virus-induced encephalitis.

Material/Methods

From January 2012 to June 2013, 112 patients with virus-induced encephalitis (the case group and 109 healthy individuals (the control group) were recruited for the purposes of this study. The functional variations that IL-4 and IL-10 genes exhibit were detected through the use of a function analysis and selection tool for single-nucleotide polymorphisms (FASTSNP). The genotypes of IL-4 were rs2227283 and IL-4 rs2227288, and the genotypes of IL-10 were rs1800871 and IL-10 rs1800872. These genotypes were respectively assessed using direct sequencing.

Results

IL-4 rs2227283 and IL-10 rs1800871 have no correlation in with risk of virus-induced encephalitis (both P>0.05)

GA and AA genotypes were related to IL-4 rs2227288 and GT, while TT and GT + TT genotypes were related to IL-10 rs1800872. These were highlighted as being risk factors in virus-induced encephalitis (all P<0.05). However, the duration of fever, white blood cell (WBC) count, C-reactive protein (CRP), neutrophils, and lymphocytes and monocytes of virus-induced encephalitis patients with IL-4 rs2227288 and IL-10 rs1800872 all displayed significant differences (all P<0.05). Frequencies of GAGT and CAGT haplotypes were evaluated and deemed to be of statistical significance and subsequently were highlighted as being risk factors in virus-induced encephalitis (all P<0.05).

Conclusions

IL-4 rs2227288 and IL-10 rs1800872 may contribute to an increased risk for virus-induced encephalitis. Through use of direct sequencing, we showed that genotypes of IL-4 rs2227288 and IL-10 rs1800872 may have particular host susceptibility to virus-induced encephalitis.

Maternal Interleukin Genotypes Are Associated With NICU Outcomes Among Low-Birth-Weight Infants

BACKGROUND

Maternal interleukin (IL) single nucleotide polymorphisms (SNPs) are associated with obstetrical outcomes. Conversely, infant SNPs are associated with subsequent neonatal intensive care unit (NICU) outcomes. Little is known about relationships between maternal SNPs and neonatal outcomes.

PURPOSE

To examine the relationships between maternal IL genotypes and neonatal outcomes.

METHODS

An ancillary study was conducted among mothers ( N = 63) who delivered very low-birth-weight infants ( N = 74). Maternal DNA was extracted from breast milk and genotyped. Outcomes included fecal calprotectin, length of stay, scores for neonatal acute physiology with perinatal extension (SNAPPE-II), weight gain, oxygen needs, necrotizing enterocolitis, intraventricular hemorrhage, sepsis, retinopathy of prematurity, blood transfusions, and feeding intolerance. Multivariate analyses examined the relationships between maternal IL SNPs and outcomes, controlling for gestational age and the ratio of maternal milk to total milk.

RESULTS

Absence of a minor allele in 2 IL6 SNPs was associated with fecal calprotectin ( p = .0222, p = .0429), length of stay ( p = .0158), SNAPPE-II ( p = .0497), weight gain ( p = .0272), and days on oxygen ( p = .0316). IL6 genotype GG (rs1800795) was associated with length of stay ( p = .0034) and calprotectin ( p = .0213). Minor-allele absence in 2 IL10 SNPs was associated with days on oxygen ( p = .0320). There were associations between IL10 genotype TT (rs1800871) and calprotectin ( p = .0270) and between IL10 genotypes AA (rs1800872 and rs1800896) and calprotectin ( p = .0158, p = .0045).

CONCLUSION

Maternal IL SNPs are associated with NICU outcomes. A potential clinical application includes an antenatal risk profile to identify neonatal needs.

Effect of Promoter Polymorphisms on Cytokine Concentration in Preterm Breast Milk and Subsequent Infant Outcomes

BACKGROUND

Breast milk concentrations of immune components are variable between women and interleukin (IL) differences may be associated with infant outcomes. Molecular mechanisms for milk variability remain unknown.

OBJECTIVE

The aims were to (1) examine the relationship between maternal IL genotypes and milk concentrations of IL4, IL6, and IL10, (2) describe the trajectories of milk IL change, (3) examine whether maternal IL genotypes predict IL trajectories and/or average weekly IL concentration, and (4) examine if weekly IL levels and/or IL trajectories are associated with infant outcomes.

METHODS

Milk aliquots were collected from each feeding of mother's own milk and pooled weekly. DNA was extracted from 1 sample of each mother's breast milk whey (n = 64), and single nucleotide polymorphisms (SNPs) of IL genes were genotyped. Milk IL concentrations were measured and trajectory analysis examined IL milk change over time. Multivariate breast milk IL concentration analyses controlled for gestational age and prepregnancy body mass index. Multivariate infant outcome (n = 73) analyses controlled for gestational age and the ratio of human milk to total milk.

RESULTS

Trajectory analysis resulted in linear group shapes, with 2 distinct subgroups in IL6 and 3 subgroups in IL4 and IL10. Trajectory groups trended toward significance with calprotectin, intraventricular hemorrhage, and blood transfusions. Multivariate analyses resulted in trending associations between maternal SNPs and subsequent IL6 and IL10 milk levels. There was a trending relationship between IL milk levels and both fecal calprotectin and intraventricular hemorrhage.

CONCLUSION

Maternal IL SNPs may affect IL breast milk levels and IL milk levels may be associated with infant outcomes.

Association of interleukin-10 gene promoter polymorphisms with recurrent pregnancy loss: a meta-analysis

PURPOSE

It has been reported single-nucleotide polymorphisms (SNPs) of the IL-10 promoter might be associated with the susceptibility to recurrent pregnancy loss (RPL). Owing to the inconclusive results, we conducted a meta-analysis to systematically summarize and clarify the association between the IL-10 promoter SNPs and RPL risk.

METHODS

A systematic search of studies on the association of the three SNPs with RPL was conducted in PubMed and Embase. Odds ratios (ORs) and 95 % confidence intervals (95 % CIs) were used to pool the effect size.

RESULT

Eleven case-control studies on rs1800896, seven studies on rs1800871, and eight studies on rs1800872 were included. A significant association was identified between IL-10 rs1800896 with RPL risk (G versus A: OR = 1.21, 95 % CI 1.09-1.35). No evidence of association was found between rs1800871 and RPL when restricted to those studies in Hardy-Weinberg equilibrium in controls (T versus C: OR = 1.25, 95 % CI 0.76-2.06). No statistical association was demonstrated between rs1800872 and RPL (C versus A: OR = 1.08, 95 % CI 0.83-1.42).

CONCLUSIONS

IL-10 rs1800896 significantly increases the risk of RPL, while rs1800872 is not correlated with RPL risk. No significant association is demonstrated between rs1800871 and RPL risk but this requires further investigation.

IL-10 gene promoter and intron polymorphisms and changes in IL-10 secretion in women with idiopathic recurrent miscarriage

STUDY QUESTION

Is recurrent pregnancy loss (RPL) associated with polymorphisms in the promoter and intron regions of the interleukin-10 (IL-10) gene?

SUMMARY ANSWER

IL-10 rs1518111 was found to be associated with RPL but the commonly studied promoter variants rs1800872, rs1800871 and 1800896 were not.

WHAT IS KNOWN ALREADY

Reduced expression of IL-10 is implicated in RPL, due to defective maternal immune tolerance (causing early miscarriages) or placental vascular insufficiency (causing late losses). IL-10 production is in part inherited, and IL-10 gene variants associated with reduced IL-10 expression have been analyzed for their association with RPL, often with inconclusive results.

STUDY DESIGN, SIZE, DURATION

A retrospective case-control study was performed between January 2011 and April 2012. The subjects comprised 296 RPL cases and 305 control women.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Genotyping of the IL-10 intron (rs1878672, rs3024492, rs1554286, rs1518111, rs3024491, rs3024490) and promoter (rs1800872, rs1800871, rs1800896) variants was done by real-time PCR, with defined clusters.

MAIN RESULTS AND THE ROLE OF CHANCE

A higher minor allele frequency (MAF) of rs1518111 (P = 0.03) was in seen RPL cases; but the MAFs of the remaining SNPs were comparable between cases and controls. Setting the homozygous major allele genotype (1/1) as the reference, significantly higher frequencies of heterozygous rs1554286 and rs1800872, and homozygous rs1800896 genotype carriers, and a reduced frequency of homozygous rs1518111 genotype carriers, were seen in RPL cases, while the distribution of the remaining genotypes were comparable between cases and controls. Serum IL-10 levels were significantly reduced in RPL cases compared with control women (P = 0.002), and this correlated with rs1518111 and rs1800871 genotypes in both groups, and with the rs1800872 genotype among control women. A nine-locus (rs1878672, rs3024492, rs1554286, rs1518111, rs3024491, rs3024490, rs1800872, rs1800871 and rs1800896) haploview analysis demonstrated an increased frequency of haplotype 112112121 in RPL cases, thus conferring a disease susceptibility nature to this haplotype.

LIMITATIONS, REASONS FOR CAUTION

The main limitation of this study was that it was limited to Bahraini Arabs, thereby necessitating parallel studies of other ethnic groups. Another limitation is the study design, which prompts speculation on whether it is a cause-effect relationship.

WIDER IMPLICATIONS OF THE FINDINGS

While the lack of association of the various IL-10 promoter variants with RPL was in agreement with reports from varied ethnic groups, this is the first study to confirm the association between IL-10 rs151811 intronic variant and RPL.

STUDY FUNDING/COMPETING INTEREST(S)

The study was funded by grants from the Arabian Gulf University Research Fund. None of the authors report any competing interests.

Alterations in inflammatory, antiviral and regulatory cytokine responses in peripheral blood mononuclear cells from pregnant women with asthma

BACKGROUND & OBJECTIVE

Severe asthma exacerbations during pregnancy are a common complication leading to poor health outcomes for both the mother and the baby. Asthma exacerbations are caused most frequently by respiratory viruses. A balance between antiviral and inflammatory immune responses is critical during pregnancy; the balance may be altered by asthma and respiratory virus infection.

METHODS

Peripheral blood mononuclear cells (PBMCs) were isolated from (i) non-pregnant healthy controls, (ii) pregnant non-asthmatics, (iii) post-partum non-asthmatics, (iv) non-pregnant asthmatics (v) pregnant asthmatics, and (vi) post-partum asthmatics. Cells were cultured in vitro with the mitogen phytohaemagglutinin or with a strain of the 2009 pandemic swine influenza. Interferon (IFN)-γ, interleukin (IL)-10 and IL-17 protein were measured from culture supernatant. Neutrophil counts were obtained in samples from pregnant and post-partum women.

RESULTS

Following the phytohaemagglutinin stimulation of PBMCs, pregnant asthmatics had significantly higher IL-17 and significantly lower IFN-γ responses compared with healthy non-pregnant women. Following infection with influenza, a significant reduction was also observed in IFN-γ and IL-10 production from PBMC of pregnant asthmatics. The IL-17 response to phytohaemagglutinin correlated with the neutrophil percentage. Differences in IFN-γ, IL-10 and IL-17 were found to persist for at least 6 months post-partum.

CONCLUSIONS

A reduction in antiviral and regulatory immunity with increased inflammation during pregnancy occurs in PBMC from pregnant women with asthma. This novel information may relate to the increased susceptibility and disease severity to respiratory virus infections observed during pregnancy.

An integrative view on the physiology of human early placental villi

The placenta is an indispensable organ for intrauterine protection, development and growth of the embryo and fetus. It provides tight contact between mother and conceptus, enabling the exchange of gas, nutrients and waste products. The human placenta is discoidal in shape, and bears a hemo-monochorial interface as well as villous materno-fetal interdigitations. Since Peter Medawar's astonishment to the paradoxical nature of the mother-fetus relationship in 1953, substantial knowledge in the domain of placental physiology has been gathered. In the present essay, an attempt has been made to build an integrated understanding of morphological dynamics, cell biology, and functional aspects of genomic and proteomic expression of human early placental villous trophoblast cells followed by a commentary on the future directions of research in this field.

The role of inflammatory pathway genetic variation on maternal metabolic phenotypes during pregnancy

Background

Since mediators of inflammation are associated with insulin resistance, and the risk of developing diabetes mellitus and gestational diabetes, we hypothesized that genetic variation in members of the inflammatory gene pathway impact glucose levels and related phenotypes in pregnancy. We evaluated this hypothesis by testing for association between genetic variants in 31 inflammatory pathway genes in the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) cohort, a large multiethnic multicenter study designed to address the impact of glycemia less than overt diabetes on pregnancy outcome.

Results

Fasting, 1-hour, and 2-hour glucose, fasting and 1-hour C-peptide, and HbA1c levels were measured in blood samples obtained from HAPO participants during an oral glucose tolerance test at 24-32 weeks gestation. We tested for association between 458 SNPs mapping to 31 genes in the inflammatory pathway and metabolic phenotypes in 3836 European ancestry and 1713 Thai pregnant women. The strongest evidence for association was observed with TNF alpha and HbA1c (rs1052248; 0.04% increase per allele C; p-value = 4.4×10⁻⁵), RETN and fasting plasma glucose (rs1423096; 0.7 mg/dl decrease per allele A; p-value = 1.1×10⁻⁴), IL8 and 1 hr plasma glucose (rs2886920; 2.6 mg/dl decrease per allele T; p-value = 1.3×10⁻⁴), ADIPOR2 and fasting C-peptide (rs2041139; 0.55 ug/L decrease per allele A; p-value = 1.4×10⁻⁴), LEPR and 1-hour C-peptide (rs1171278; 0.62 ug/L decrease per allele T; p-value = 2.4×10⁻⁴), and IL6 and 1-hour plasma glucose (rs6954897; −2.29 mg/dl decrease per allele G, p-value = 4.3×10⁻⁴).

Conclusions

Based on the genes surveyed in this study the inflammatory pathway is unlikely to have a strong impact on maternal metabolic phenotypes in pregnancy although variation in individual members of the pathway (e.g. RETN, IL8, ADIPOR2, LEPR, IL6, and TNF alpha,) may contribute to metabolic phenotypes in pregnant women.

Interleukin-10 promoter microsatellite polymorphisms influence the immune response to heparin and the risk of heparin-induced thrombocytopenia

INTRODUCTION

Heparin-induced thrombocytopenia (HIT) results from an atypical immune response with synthesis of IgG antibodies (Abs) to platelet factor 4/heparin complexes (PF4/H), and probably involves both B and T cells. We investigated whether 3 single nucleotide polymorphisms (SNPs), rs1800896 (-1082G/A), rs1800871 (-819C/T) and rs1800872 (-592C/A) and the polymorphic CA repeat microsatellites IL10R [5325CA(11_15)] and IL10G [8134CA(14_29)] are associated with the synthesis of Abs to PF4/heparin and HIT.

MATERIALS AND METHODS

Eighty-two patients with definite HIT and two control groups were studied. The first control group (Ab(neg)) consisted of 85 patients without Abs to PF4/heparin after cardiopulmonary bypass (CPB). The second control group (Ab(pos)) consisted of 84 patients who had developed significant levels of PF4-specific antibodies after CPB, but without HIT.

RESULTS

Allele frequencies of the 3 SNPs were similar in HIT patients and controls. Fourteen alleles in IL10G (G16 to G29) and 3 alleles in IL10R (R13 to R15) were defined. The short G20 allele of IL10G was more frequent in Ab(neg) patients (8.2%) than in Ab(pos) (2.9%) and HIT patients (3%). It thereby appeared to protect against developing Abs to PF4/heparin (OR 0.29; 95% CI [0.12-0.70], p=0.006). Combined haplotypes cH1/cH8 comprising the short G20 + R13 alleles were less frequent in HIT (OR 0.33; 95% CI [0.11-0.97], p=0.036), and levels of Abs to PF4 in Ab(pos) patients were lower in cH1/cH8 subjects (p=0.019).

CONCLUSION

These results suggest that IL10 promoter microsatellite polymorphisms might influence the immune response against PF4/heparin and the risk of HIT.

A common polymorphism in NR1H2 (LXRbeta) is associated with preeclampsia

Background

Preeclampsia is a frequent complication of pregnancy and a leading cause of perinatal mortality. Both genetic and environmental risk factors have been identified. Lipid metabolism, particularly cholesterol metabolism, is associated with this disease. Liver X receptors alpha (NR1H3, also known as LXRalpha) and beta (NR1H2, also known as LXRbeta) play a key role in lipid metabolism. They belong to the nuclear receptor superfamily and are activated by cholesterol derivatives. They have been implicated in preeclampsia because they modulate trophoblast invasion and regulate the expression of the endoglin (CD105) gene, a marker of preeclampsia. The aim of this study was to investigate associations between the NR1H3 and NR1H2 genes and preeclampsia.

Methods

We assessed associations between single nucleotide polymorphisms of NR1H3 (rs2279238 and rs7120118) and NR1H2 (rs35463555 and rs2695121) and the disease in 155 individuals with preeclampsia and 305 controls. Genotypes were determined by high-resolution melting analysis. We then used a logistic regression model to analyze the different alleles and genotypes for those polymorphisms as a function of case/control status.

Results

We found no association between NR1H3 SNPs and the disease, but the NR1H2 polymorphism rs2695121 was found to be strongly associated with preeclampsia (genotype C/C: adjusted odds ratio, 2.05; 95% CI, 1.04-4.05; p = 0.039 and genotype T/C: adjusted odds ratio, 1.85; 95% CI, 1.01-3.42; p = 0.049).

Conclusions

This study provides the first evidence of an association between the NR1H2 gene and preeclampsia, adding to our understanding of the links between cholesterol metabolism and this disease.

Interleukin-10 microsatellite variants and the risk of acute coronary syndrome among Tunisians

The objective of the study was to investigate the association of interleukin (IL)-10 promoter microsatellite polymorphisms, linked with altered IL-10 secretion, with the susceptibility to acute coronary syndrome (ACS) in adult Tunisian patients. We genotyped 291 ACS patients and 291 age-, gender- and ethnically matched control subjects for the microsatellites IL-10R [X78437.2g.5325CA(11_15)] and IL-10G [X78437.2g.8134CA(14_29)] by PCR-based assays. Haplotypes were reconstructed using maximum likelihood method. Regression analysis was used in determining the risk imparted by specific IL-10 genotypes and haplotypes. A significant decrease in IL-10G12 (24 CA repeats) (P<0.001; OR=0.465) and IL-10G15 (27 CA repeats) (P=0.043; OR=0.232), and a significant increase in the low IL-10 producer allele, IL-10R3 (14 CA repeats) (P=0.049; OR=1.461), microsatellites were seen in the ACS group compared with controls. Of the possible 14 haplotypes constructed, there was an enrichment of the R2G9 (13CA vs. 21CA) haplotype in controls [P=0.019; adjusted OR (95% CI)=0.67 (0.48-0.94)] and R2G15 (13CA vs. 27CA) haplotype in cases [P=0.042; adjusted OR (95% CI)=5.29 (1.06-26.30)], thus assigning a protective and susceptible nature to these haplotypes respectively. The differential association of IL-10 microsatellite alleles and haplotypes with ACS suggests that IL-10 contributes to ACS pathogenesis. While the functional attributes of these microsatellite markers remain to be seen, it is likely that they have distinct functional properties (altered IL-10 secretion), which in turn affect the susceptibility to ACS development.

Examination of genetic polymorphisms in newborns for signatures of sex-specific prenatal selection

Success rate in human pregnancies is believed to be very low and sex-specific mechanisms may operate in prenatal loss. Assuming a sex-differential in prenatal loss exists, we examined genetic markers in biologically plausible targets in the HLA complex, other immune system-related and iron-regulatory genes in 388 healthy newborns from Wales (UK) using one sex as a control group for the other. Genotyping of 333 single nucleotide polymorphisms (SNPs) from 107 genes was achieved mainly by TaqMan assays. Twenty-two of autosomal SNPs showed frequency differences between 187 male and 201 female newborns either individually or as part of a haplotype. Of these, six markers (RXRB rs2076310, HLA complex haplotype HLA-DQA1 rs1142316-HLA-DRA rs7192-HSPA1B rs1061581, HIST1H1T rs198844, IFNG rs2069727, NKG2D rs10772266 and IRF4 heterozygosity) showed statistically robust differences between male and female newborns and multivariable modeling confirmed their independence. There were fewer males homozygote for combined wildtype genotypes of LIF rs929271, TP53 rs1042522 and MDM2 rs2279744 compared with females [OR = 0.3, 95% confidence interval (CI) = 0.1-0.8; P < 0.01] although these SNPs did not show any association individually. It is unlikely that SNPs have clinical utility as single markers in any trait with complex etiology but polygenic predictive models remain a possibility. If their validity is confirmed in larger studies of different populations and functional mechanisms of these preliminary associations are elucidated, these markers from the HLA complex, NKG2D region and cytokines may cumulatively have sufficient predictive value for susceptibility to prenatal selection in each sex.