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There is debate about the relative importance of timing of stressful events prenatally and over the life course and risk for subsequent depressive/anxious illness. The aim of this study was to examine the relative roles of prenatal stress and postnatal stress trajectories in predicting depression and anxiety in early adulthood in males and females. Exposure to life stress events was examined in the Western Australian Pregnancy Cohort (Raine) Study during pregnancy and ages 1, 2, 3, 5, 8, 10, 14, and 17 years. At age 20, offspring completed the Depression Anxiety Stress Scale. Prenatal stress and trajectories of stress events from age 1 to 17 were analyzed in linear regression analyses. Five postnatal stress trajectories were identified. In females, medium to high chronic stress exposure or exposure during puberty/adolescence predicted depression and anxiety symptoms while low or reduced stress exposure over the life course did not, after adjustment for relevant confounders. High stress early in pregnancy contributed to male depression/anxiety symptoms independent of postnatal stress trajectory. In females, postnatal stress trajectory was more important than prenatal stress in predicting depression/anxiety symptoms. Interventions focused on reducing and managing stress events around conception/pregnancy and exposure to chronic stress are likely to have beneficial outcomes on rates of depression and anxiety in adults.

Background: Activation of the hypothalamic-pituitary-adrenal (HPA) axis has been associated with higher levels of cardiovascular (CVD) risk factors in adults. This study aimed to assess the relation between measures of HPA axis activity under resting conditions and CVD risk factors in a general population of adolescents at 17 years., Methods: A total of 1134 adolescents from the Western Australian Pregnancy Cohort (Raine) Study had phenotypic and socio-demographic data. The associations between HPA axis measures (plasma ACTH, total cortisol, calculated free cortisol, corticosteroid binding globulin (CBG), and salivary cortisol) and a range of cardiovascular risk factors were examined using multivariable linear regression models, with adjustment for gender, adiposity, birth weight, gestational age, and socio-behavioural factors., Results: Plasma total cortisol was positively associated with systolic blood pressure (SBP) (p=0.011), total cholesterol, HDL-cholesterol, and triglycerides (all p<0.001), and hs-CRP (p=0.047). Salivary cortisol was associated positively with HDL-C (p=0.033) and negatively with LDL-cholesterol (p=0.016); plasma calculated free cortisol was positively associated with triglycerides (p=0.006); plasma CBG was positively associated with total cholesterol and HDL-cholesterol (both p<0.001), LDL-cholesterol (p=0.022), and hs-CRP (p=0.001). After correction for multiple comparisons, significant associations remained for total cortisol with total cholesterol, HDL-C, and triglycerides; for calculated free cortisol with triglycerides; and for CBG with HDL-C, total cholesterol, and hs-CRP. Plasma ACTH was not associated with any cardiovascular risk factor. There was no association between BMI and any measure of HPA axis activity., Conclusion: In an adolescent population, HPA axis measures under resting conditions are associated with a range of CVD risk factors. Clarification of the mechanisms underlying these associations in adolescence would be an important step in understanding the evolution of adult CVD., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

In older adults, high-normal circulating cortisol levels are associated with lower bone mass, but relationships between hypothalamic-pituitary-adrenal axis function and peak bone mass in young adults have not been examined. We studied 411 male and 390 female participants in the Western Australia Pregnancy Cohort (Raine) Study. At 18years of age, participants underwent a Trier Social Stress Test (TSST) with measurement of plasma and salivary cortisol at baseline and at multiple time points after stress. Cortisol responses were classified as anticipatory responder (significant fall in cortisol during the test), reactive responder (significant increase) or non-responder. At 20years, total body bone mineral content (BMC) and density (BMD) were measured by DXA. In males, after adjustment for weight, height (for BMC and bone area only), alcohol and smoking, there was a significant inverse relationship between both plasma and salivary cortisol measured at baseline in the TSST and each of BMC and BMD, such that each additional 10% of salivary cortisol was associated with reductions of 6.9g (95% CI -11.7, -2.2) in BMC, and 1.8mg/cm(2) (95% CI -3.3, -0.4) in BMD. Males classified as anticipatory responders in the TSST had 3.2% lower BMC (adjusted mean±SE: 3131±28 vs. 3233±18g, P=0.006) and 2.5% lower BMD (1108±9 vs. 1136±6mg/cm(2), P=0.022) than reactive responders. In females, there were no significant relationships between baseline cortisol or TSST responses and BMC or BMD in covariate-adjusted analyses. We conclude that in young males (but not females), higher circulating cortisol at the baseline of the stress test and an anticipatory responder pattern on the TSST are associated with lower total body bone mass., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Dysregulation of the biological stress response system has been implicated in the development of psychological, metabolic, and cardiovascular disease. Whilst changes in stress response are often quantified as an increase or decrease in cortisol levels, three different patterns of stress response have been reported in the literature for the Trier Social Stress Test (TSST) (reactive-responders (RR), anticipatory-responders (AR) and non-responders (NR)). However, these have never been systematically analyzed in a large population-based cohort. The aims of this study were to examine factors that contribute to TSST variation (gender, oral contraceptive use, menstrual cycle phase, smoking, and BMI) using traditional methods and novel analyses of stress response patterns. We analyzed the acute stress response of 798, 18-year-old participants from a community-based cohort using the TSST. Plasma adrenocorticotrophic hormone, plasma cortisol, and salivary cortisol levels were quantified. RR, AR, and NR patterns comprised 56.6%, 26.2%, and 17.2% of the cohort, respectively. Smokers were more likely to be NR than (RR or AR; adjusted, p < 0.05). Overweight and obese subjects were less likely to be NR than the other patterns (adjusted, p < 0.05). Males were more likely to be RR than NR (adjusted, p = 0.05). In addition, we present a novel AUC measure (AUCR), for use when the TSST baseline concentration is higher than later time points. These results show that in a young adult cohort, stress-response patterns, in addition to other parameters vary with gender, smoking, and BMI. The distribution of these patterns has the potential to vary with adult health and disease and may represent a biomarker for future investigation.

The prenatal period is recognised as a critical period for later behavioural development. This study aimed to elucidate how an adverse prenatal environment, as defined by the presence of a number of known prenatal risk factors, would influence mental health trajectories in children to 14 years of age. The Raine Study provided comprehensive data from 2,900 pregnancies. Offspring were followed up at ages 2, 5, 8, 10, and 14 years using the Child Behaviour Checklist (CBCL). We used linear mixed regression models with random intercept and slope (random effects models) to examine the extent to which the predictor variables considered influenced changes in continuous CBCL total, internalising, and externalising T scores from ages 2 to 14. In the final multivariate models, increased offspring CBCL T scores were significantly predicted by the mother not finishing high school, smoking during pregnancy, having a total family income below the poverty line, being diagnosed with gestational hypertension and experiencing stressful life events during pregnancy. Conversely, as maternal age increased, CBCL T scores were significantly decreased. Child age also significantly interacted with maternal education, total family income, and maternal stressful life events, such that these variables predicted increases in CBCL scores from age 2 to age 10, and from age 2 to age 14 years. In the Raine Study sample, children who experienced adverse prenatal environments experienced increased levels of problem behaviours in childhood, and more problematic mental health trajectories. Maternal health risk behaviours and other psychosocial variables more commonly affected child behaviour than obstetric complications.

Objectives: Poor dietary habits have been implicated in the development of nonalcoholic fatty liver disease (NAFLD); however, little is known about the role of specific dietary patterns in the development of NAFLD. We examined prospective associations between dietary patterns and NAFLD in a population-based cohort of adolescents., Methods: Participants in the Western Australian Pregnancy Cohort (Raine) Study completed a food frequency questionnaire at 14 years and had liver ultrasound at 17 years (n=995). Healthy and Western dietary patterns were identified using factor analysis and all participants received a z-score for these patterns. Prospective associations between the dietary pattern scores and risk of NAFLD were analyzed using multiple logistic regression., Results: NAFLD was present in 15.2% of adolescents. A higher Western dietary pattern score at 14 years was associated with a greater risk of NAFLD at 17 years (odds ratio (OR) 1.59; 95% confidence interval (CI) 1.17-2.14; P<0.005), although these associations were no longer significant after adjusting for body mass index at 14 years. However, a healthy dietary pattern at 14 years appeared protective against NAFLD at 17 years in centrally obese adolescents (OR 0.63; 95% CI 0.41-0.96; P=0.033), whereas a Western dietary pattern was associated with an increased risk of NAFLD., Conclusions: A Western dietary pattern at 14 years in a general population sample was associated with an increased risk of NAFLD at 17 years, particularly in obese adolescents. In centrally obese adolescents with NAFLD, a healthy dietary pattern may be protective, whereas a Western dietary pattern may increase the risk.

Objective: The current prevalence of mental health problems in Western populations is approximately 20% and half of all adult mental health disorders are estimated to originate in adolescence. Diet plays an important role in modulating psychological wellbeing and B-vitamins are vital for the synthesis of neurotransmitters such as serotonin. We aimed to examine the relationship between B-group vitamins and adolescent mental health and behaviour., Methods: This is a cross-sectional analysis of the West Australian Pregnancy Cohort (Raine) Study. The 17-year follow-up included collection of a food frequency questionnaire allowing B-vitamin intake calculation. Mental health was assessed using the Youth Self Report (YSR) which measures total, internalising (withdrawn/depressed) and externalising (aggressive/delinquent) behaviour scores. Multiple linear regression was used to analyse associations between B-vitamins and mental health with adjustment for relevant confounders (n=709)., Results: Lower intake of vitamins B1, B2, B3, B5, B6, and folate was associated with higher externalising behaviour scores (p ≤ 0.05). Reduced intake of vitamin B6 and folate was associated with higher internalising behaviour scores (p ≤ 0.05)., Conclusions: Poor nutrition may contribute to the pathogenesis of mental health problems in adolescence. The role of B-vitamins requires further investigation in randomised controlled trials., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Unlabelled: Iron and cholesterol are both essential metabolites in mammalian systems, and too much or too little of either can have serious clinical consequences. In addition, both have been associated with steatosis and its progression, contributing, inter alia, to an increase in hepatic oxidative stress. The interaction between iron and cholesterol is unclear, with no consistent evidence emerging with respect to changes in plasma cholesterol on the basis of iron status. We sought to clarify the role of iron in lipid metabolism by studying the effects of iron status on hepatic cholesterol synthesis in mice with differing iron status. Transcripts of seven enzymes in the cholesterol biosynthesis pathway were significantly up-regulated with increasing hepatic iron (R(2) between 0.602 and 0.164), including those of the rate-limiting enzyme, 3-hydroxy-3-methylglutarate-coenzyme A reductase (Hmgcr; R(2) = 0.362, P < 0.002). Hepatic cholesterol content correlated positively with hepatic iron (R(2) = 0.255, P < 0.007). There was no significant relationship between plasma cholesterol and either hepatic cholesterol or iron (R(2) = 0.101 and 0.014, respectively). Hepatic iron did not correlate with a number of known regulators of cholesterol synthesis, including sterol-regulatory element binding factor 2 (Srebf2; R(2) = 0.015), suggesting that the increases seen in the cholesterol biosynthesis pathway are independent of Srebf2. Transcripts of genes involved in bile acid synthesis, transport, or regulation did not increase with increasing hepatic iron., Conclusion: This study suggests that hepatic iron loading increases liver cholesterol synthesis and provides a new and potentially important additional mechanism by which iron could contribute to the development of fatty liver disease or lipotoxicity.

Background & Aims: Hereditary haemochromatosis type 3 is caused by mutations in transferrin receptor (TFR) 2. TFR2 has been shown to mediate iron transport in vitro and regulate iron homeostasis. The aim of this study was to determine the role of Tfr2 in iron transport in vivo using a Tfr2 mutant mouse., Methods: Tfr2 mutant and wild-type mice were injected intravenously with (59)Fe-transferrin and tissue (59)Fe uptake was measured. Tfr1, Tfr2 and ferroportin expression was measured by real-time PCR and Western blot. Cellular localisation of ferroportin was determined by immunohistochemistry., Results: Transferrin-bound iron uptake by the liver and spleen in Tfr2 mutant mice was reduced by 20% and 65%, respectively, whilst duodenal and renal uptake was unchanged compared with iron-loaded wild-type mice. In Tfr2 mutant mice, liver Tfr2 protein was absent, whilst ferroportin protein was increased in non-parenchymal cells and there was a low level of expression in hepatocytes. Tfr1 expression was unchanged compared with iron-loaded wild-type mice. Splenic Tfr2 protein expression was absent whilst Tfr1 and ferroportin protein expression was increased in Tfr2 mutant mice compared with iron-loaded wild-type mice., Conclusions: A small reduction in hepatic transferrin-bound iron uptake in Tfr2 mutant mice suggests that Tfr2 plays a minor role in liver iron transport and its primary role is to regulate iron metabolism. Increased ferroportin expression due to decreased hepcidin mRNA levels is likely to be responsible for impaired splenic iron uptake in Tfr2 mutant mice., (Copyright (c) 2009 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.)

Transferrin receptor (TFR) 1 and 2 are expressed in the liver; TFR1 levels are regulated by cellular iron levels while TFR2 levels are regulated by transferrin saturation. The aims of this study were to 1) determine the relative importance of TFR1 and TFR2 in transferrin-bound iron (TBI) uptake by HuH7 human hepatoma cells and 2) characterize the role of metal-transferrin complexes in the regulation of these receptors. TFR expression was altered by 1) incubation with metal-transferrin (Tf) complexes, 2) TFR1 and TFR2 small interfering RNA knockdown, and 3) transfection with a human TFR2 plasmid. TBI uptake was measured using (59)Fe-(125)I-labeled Tf and mRNA and protein expression by real-time PCR and Western blot analysis, respectively. Fe(2)Tf, Co(2)Tf, and Mn(2)Tf increased TFR2 protein expression, indicating that the upregulation was not specifically regulated by iron-transferrin but also other metal-transferrins. In addition, Co(2)Tf and Mn(2)Tf upregulated TFR1, reduced ferritin, and increased hypoxia-inducible factor-1alpha protein expression, suggesting that TFR1 upregulation was due to a combination of iron deficiency and chemical hypoxia. TBI uptake correlated with changes in TFR1 but not TFR2 expression. TFR1 knockdown reduced iron uptake by 80% while TFR2 knockdown did not affect uptake. At 5 microM transferrin, iron uptake was not affected by combined TFR1 and TFR2 knockdown. Transfection with a hTFR2 plasmid increased TFR2 protein expression, causing a 15-20% increase in iron uptake and ferritin levels. This shows for the first time that TFR-mediated TBI uptake is mediated primarily via TFR1 but not TFR2 and that a high-capacity TFR-independent pathway exists in hepatoma cells.

Unlabelled: HFE-related hereditary hemochromatosis results in hepatic iron overload. Hepatocytes acquire transferrin-bound iron via transferrin receptor (Tfr) 1 and Tfr1-independent pathways (possibly Tfr2-mediated). In this study, the role of Hfe in the regulation of hepatic transferrin-bound iron uptake by these pathways was investigated using Hfe knockout mice. Iron and transferrin uptake by hepatocytes from Hfe knockout, non-iron-loaded and iron-loaded wild-type mice were measured after incubation with 50 nM (125)I-Tf-(59)Fe (Tfr1 pathway) and 5 microM (125)I-Tf-(59)Fe (Tfr1-independent or putative Tfr2 pathway). Tfr1 and Tfr2 messenger RNA (mRNA) and protein expression were measured by real-time polymerase chain reaction and western blotting, respectively. Tfr1-mediated iron and transferrin uptake by Hfe knockout hepatocytes were increased by 40% to 70% compared with iron-loaded wild-type hepatocytes with similar iron levels and Tfr1 expression. Iron and transferrin uptake by the Tfr1-independent pathway was approximately 100-fold greater than by the Tfr1 pathway and was not affected by the absence of Hfe. Diferric transferrin increased hepatocyte Tfr2 protein expression, resulting in a small increase in transferrin but not iron uptake by the Tfr1-independent pathway., Conclusion: Tfr1-mediated iron uptake is regulated by Hfe in hepatocytes. The Tfr1-independent pathway exhibited a much greater capacity for iron uptake than the Tfr1 pathway but it was not regulated by Hfe. Diferric transferrin up-regulated hepatocyte Tfr2 protein expression but not iron uptake, suggesting that Tfr2 may have a limited role in the Tfr1-independent pathway.

Background/aims: Transferrin receptor 2 appears to have dual roles in iron metabolism; one is signalling, the other is iron transport. It is sensitive to high levels of diferric transferrin, which is associated with disorders of iron overload. Also present in these disorders are increased levels of plasma non-transferrin-bound iron. This study sought to clarify the role of transferrin receptor 2 in the uptake of transferrin-bound and non-transferrin-bound iron., Methods: Variant Chinese Hamster Ovary (CHO) cells, transfected with transferrin receptor 2, were incubated with radio-labelled transferrin-bound or non-transferrin-bound iron. Competition studies were performed in the presence of unlabelled dimetallic transferrin; knockdown was performed using specific siRNA., Results: Cells expressing transferrin receptor 2 bound and internalised transferrin and transferrin-bound iron. Transferrin recycling occurred with an average cycling time of 11-15 min. Interestingly, the presence of transferrin receptor 2 was also associated with uptake of non-transferrin-bound iron which was inhibited by unlabelled transferrin-bound metals. Knockdown reduced transferrin-bound and non-transferrin-bound iron uptake by approximately 60%., Conclusions: Transferrin receptor 2 mediates transferrin-bound iron uptake by receptor-mediated endocytosis. It is also involved in the uptake of non-transferrin-bound iron and the inhibition of non-transferrin-bound iron uptake by diferric transferrin in CHO cells.

The liver plays a central role in iron metabolism. It is the major storage site for iron and also expresses a complex range of molecules which are involved in iron transport and regulation of iron homeostasis. An increasing number of genes associated with hepatic iron transport or regulation have been identified. These include transferrin receptors (TFR1 and 2), a ferrireductase (STEAP3), the transporters divalent metal transporter-1 (DMT1) and ferroportin (FPN) as well as the haemochromatosis protein, HFE and haemojuvelin (HJV), which are signalling molecules. Many of these genes also participate in iron regulatory pathways which focus on the hepatic peptide hepcidin. However, we are still only beginning to understand the complex interactions between liver iron transport and iron homeostasis. This review outlines our current knowledge of molecules of iron metabolism and their roles in iron transport and regulation of iron homeostasis.

Hereditary hemochromatosis type 3 is an iron (Fe)-overload disorder caused by mutations in transferrin receptor 2 (TfR2). TfR2 is expressed highly in the liver and regulates Fe metabolism. The aim of this study was to investigate duodenal Fe absorption and hepatic Fe uptake in a TfR2 (Y245X) mutant mouse model of hereditary hemochromatosis type 3. Duodenal Fe absorption and hepatic Fe uptake were measured in vivo by 59Fe-labeled ascorbate in TfR2 mutant mice, wild-type mice, and Fe-loaded wild-type mice (2% dietary carbonyl Fe). Gene expression was measured by real-time RT-PCR. Liver nonheme Fe concentration increased progressively with age in TfR2 mutant mice compared with wild-type mice. Fe absorption (both duodenal Fe uptake and transfer) was increased in TfR2 mutant mice compared with wild-type mice. Likewise, expression of genes participating in duodenal Fe uptake (Dcytb, DMT1) and transfer (ferroportin) were increased in TfR2 mutant mice. Nearly all of the absorbed Fe was taken up rapidly by the liver. Despite hepatic Fe loading, hepcidin expression was decreased in TfR2 mutant mice compared with wild-type mice. Even when compared with Fe-loaded wild-type mice, TfR2 mutant mice had increased Fe absorption, increased duodenal Fe transport gene expression, increased liver Fe uptake, and decreased liver hepcidin expression. In conclusion, despite systemic Fe loading, Fe absorption and liver Fe uptake were increased in TfR2 mutant mice in association with decreased expression of hepcidin. These findings support a model in which TfR2 is a sensor of Fe status and regulates duodenal Fe absorption and liver Fe uptake.

Background/aims: In hereditary hemochromatosis, iron-loading of hepatocytes is associated with increased iron uptake while little is known about iron release. This study aims to characterise iron release and ferroportin expression by Hfe knockout hepatocytes to determine if they contribute to iron overload in haemochromatosis., Methods: Iron release by hepatocytes from Hfe knockout, non-iron-loaded and iron-loaded wild-type mice was measured after incubation with nontransferrin-bound iron as iron-citrate., Results: Iron release and ferroportin expression by hepatocytes from Hfe knockout, non-iron-loaded and in vivo iron-loaded wild-type mice were similar although, nontransferrin-bound iron uptake was significantly increased in Hfe knockout hepatocytes and decreased in iron-loaded wild-type hepatocytes compared with non-iron-loaded wild-type cells. When expressed as a percentage of total iron uptake, iron release was decreased in Hfe knockout hepatocytes (4.6+/-0.7 versus 13.7+/-1.2%, P<0.0001) and increased in iron-loaded wild-type hepatocytes (29.5+/-0.5 versus 13.5+/-0.7%; P<0.0001) compared with wild-type hepatocytes. In contrast, in vitro iron-loading increased iron release and ferroportin expression by both Hfe knockout and wild-type hepatocytes., Conclusions: Hfe knockout hepatocytes accumulate iron as a result of limited iron export and enhanced iron uptake. The correlation between iron release and ferroportin expression suggests that iron export in hepatocytes is mediated by ferroportin.

Background: A common polymorphism in the hepatic lipase (HL) gene promoter, -514C/T, affecting enzyme activity, has been associated with alterations in plasma lipoprotein levels. However a relationship with coronary heart disease (CHD) is less well documented., Design and Methods: We studied HL -514 C/T in 562 Caucasian CHD patients aged under 50 years and in 642 Caucasian community recruited subjects without historical evidence of CHD., Results: Male CHD subjects (n = 490) had a 41% carrier rate for the C to T substitution, compared with 33% in corresponding controls (n = 330), [OR = 1.42 (95% CI:1.06-1.90), P < 0.02], T allele frequencies being 0.231 and 0.177 respectively [OR = 1.39 (1.08-1.78), P < 0.01]. In male CHD subjects, the T allele was associated with higher HDL-cholesterol (HDL-C) (CC: 0.95 +/- 0.24 (SD); CT: 1.04 +/- 0.41; TT: 1.01 +/- 0.20 mmol/l, P = 0.02, ANOVA) but the trend was not significant in females. In male CHD patients the T allele was more frequently encountered in those with high (> 4.5 mmol/l) than in those with low triglycerides [68% vs. 39%, OR = 3.13 (1.54-6.67), P = 0.001]. In community control subjects, the T allele was associated with a trend to higher HDL-C levels, the significance varying between subgroups while, in males, serum total and LDL-cholesterol were significantly lower in T homozygotes than in the other two genotypes (LDL-C: 2.73 +/- 0.63 vs. 3.56 +/- 0.95 mmol/l; P = 0.01). During the course of this study, a previously unreported promoter region polymorphism was found exclusively on -514C chromosomes (-592A/G, A allele frequency 0.108, 95% CI 0.09 - 0.126). It can lead to mistyping of C as T alleles in C/T heterozygotes, resulting in overestimation of -514 T homozygotes., Conclusions: The T allele of the hepatic lipase -514 C/T polymorphism is associated with changes in plasma lipids. The superficially paradoxical predisposition to CHD in males is attributable to impairment of TG rich lipoprotein metabolism and reverse cholesterol transport.

Background: Recently, we localized the Human Poliovirus Receptor Related 2 Gene (PRR2) 17kb centromeric to the gene for apolipoprotein E (APOE). Common polymorphisms in the latter have been found, in some studies, to be related to coronary heart disease (CHD) but the PRR2 gene has not been studied in this context. Here, we examined relationships between a PRR2 Sau96I (A/G) polymorphism, the epsilon2, 3 and 4 alleles of APOE and CHD., Design and Methods: Consecutive Caucasian patients (n = 640) < 50 years with angiographically documented coronary obstructive disease and/or with unequivocal myocardial infarction were compared with 624 control subjects, aged 30-50 years, randomly selected from the community and without a history of CHD., Results: An excess of PRR2-A homozygotes was observed in cases (20% vs. 15%; OR 1.4, CI 1.04-1.86, P = 0.026) particularly in those with single vessel disease (OR 1.7, CI 1.2-2.4, P <0.01). The A allele was in linkage disequilibrium with the epsilon4 allele and the G allele with the epsilon2. Overrepresentation of the A allele and underrepresentation of the G allele in the CHD group did not reach significance (P = 0.054). While the epsilon2 allele was underrepresented in the CHD group (OR 0.64, CI 0.46-0.89, P = 0.009), the epsilon4 allele was not significantly overrepresented., Conclusion: The relationship between the PRR2 Sau96I (A/G) polymorphism and early onset coronary artery disease may be due to linkage disequilibrium with the APOE gene and underrepresentation, or a protective effect, of the epsilon2 allele. Alternatively, since A allele homozygosity is particularly overrepresented, the relationship could be more direct, perhaps through a viral association.

Objective: This study examined the frequency of the Lys198Asn polymorphism in the endothelin-1 (ET-1) gene in women with pre-eclampsia and normal pregnancy; and its contribution to levels of plasma ET-1 and blood pressure., Design and Methods: This was a retrospective study examining the frequency of the ET-1 Lys198Asn polymorphism in 72 proteinuric pre-eclamptics and 81 normal pregnant women. Height, weight, blood pressure and plasma ET-1 were measured antenatally and at 6 weeks post-partum. Using specific mutagenic primers, the frequency of the G/G (normal), G/T heterozygote and T/T (mutant) genotypes of the Lys198Asn polymorphism were examined., Results: The polymorphism was not associated with pre-eclampsia. However, in the combined pregnant groups after correction for BMI and group, a significant effect of the T-allele (T/T,G/T) on systolic blood pressure was found (121 +/- 1.5 mmHg compared with 116 +/- 1.3 mmHg in the G/G homozygotes). A significant interaction was found between the T-allele and pregnancy in determining systolic blood pressure, so that the effect was no longer seen post-partum. Pregnant women with the T/T genotype had significantly elevated plasma ET-1 levels 5.8 pg/ml [confidence interval (CI) 3.7-9.1] compared with 3.1 pg/ml (CI 2.6-3.8) in the G/T heterozygotes and 3.6 pg/ml (CI 3.0-4.1) in the normal G/G homozygotes., Conclusion: The Lys198Asn polymorphism does not directly contribute to the incidence of pre-eclampsia. However, the association of the T-allele with raised blood pressure and the T/T genotype with increased plasma ET-1 levels suggest that this polymorphism may interact with other genes or environmental factors to sensitize pregnant women to develop pre-eclampsia.

As MHC genes are potent determinants of susceptibility to immunopathological diseases, the mapping of SAPK2a (CSBP) and SAPK4 to chromosome 6p 21.2-21.3 suggested that these genes may mediate the effects of the MHC on disease. Here we describe the genomic structure and localisation of both genes approximately 2.3Mb centromeric of HLA-DP. Examination of the complete coding region and selected intronic regions of SAPK2a and SAPK4 from 22 human EBV-transformed B-cell lines of different MHC haplotypes and racial background revealed complete sequence conservation. There were no notable differences in levels of expression of SAPK2a and SAPK4 mRNA in cell lines of different MHC haplotypes or racial origin. Examination of the SAPK2a and SAPK4 sequences from two chimpanzees revealed 3 nucleotide differences between human and chimpanzee in each gene resulting in only one amino acid change in SAPK4, and 6 nucleotide substitutions plus 2 deletions in 600bp of intronic sequence from SAPK4. This highlights the selective pressure placed on these genes to maintain their protein sequence, but does not favour a role in genetic regulation of disease or provide evidence of linkage disequilibrium with the MHC.