Discovering how environmental exposures alter genes could lead to new treatments for chronic illnesses

First report of tinea corporis caused by Trichophyton quinckeanum in Iran and its antifungal susceptibility profile

Background and Purpose

Trichophyton quinckeanum, a known zoophilic dermatophyte responsible for favus form in rodents and camels, is occasionally reported to cause human infections.

Case Report

This study aimed to report a case of tinea corporis caused by T. quinckeanum that experienced annular erythematous pruritic plaque with abundant purulent secretions. In June 2021, a 15-year-old girl with an erythematous cup shape lesion on the right wrist bigger than 3 cm in diameter was examined for tinea corporis. Since March, 2016 her family has kept several camels at home. Direct examination of skin scraping and purulent exudates revealed branching septal hyaline hyphae and arthrospore. Morphological evaluation of the recovered isolate from the culture and sequencing of ITS1-5.8S rDNA-ITS2 region resulted in the identification of T. quinckeanum. Antifungal susceptibility testing showed that this isolate had low minimum inhibitory concentration (MIC) values for luliconazole, terbinafine, and tolnaftate, but high MICs to itraconazole, fluconazole, posaconazole, miconazole, isavuconazole, ketoconazole, clotrimazole, and griseofulvin. However, the patient was successfully treated with oral terbinafine and topical ketoconazole.

Conclusion

It can be said that T. quinckeanum is often missed or misidentified due to its morphological similarity to T. mentagrophytes/T. interdigitale or other similar species. This dermatophyte species is first reported as the cause of tinea corporis in Iran. As expected, a few months after our study, T. quinckeanum was detected in other areas of Iran, in a few cases.

The potential roles of genetic factors in predicting ageing-related cognitive change and Alzheimer's disease

Alzheimer's disease (AD) is a complex neurological disorder of uncertain aetiology, although substantial research has been conducted to explore important factors related to risk of onset and progression. Both lifestyle (e.g., complex mental stimulation, vascular health) and genetic factors (e.g., APOE, BDNF, PICALM, CLU, APP, PSEN1, PSEN2, and other genes) have been associated with AD risk. Despite more than thirty years of genetic research, much of the heritability of AD is not explained by measured loci. This suggests that the missing heritability of AD might be potentially related to rare variants, gene-environment and gene-gene interactions, and potentially epigenetic modulators. Moreover, while ageing is the most substantial factor risk for AD, there are limited longitudinal studies examining the association of genetic factors with decline in cognitive function due to ageing and the preclinical stages of this condition. This review summarises findings from currently available research on the genetic factors of ageing-related cognitive change and AD and suggests some future research directions.

Prevalence of Common Gynecological Conditions in the Middle East: Systematic Review and Meta-Analysis

Introduction: High prevalence of gynecological conditions in women of Middle Eastern origin is reported, likely due to regional risk factors and mediators. The objective of this systematic review and meta-analysis is to investigate the prevalence of polycystic ovary syndrome (PCOS), endometriosis, uterine fibroids, and adenomyosis in women of Middle Eastern origin. Methods: MEDLINE, EMBASE, PsycINFO, Global Health, and Google Scholar databases were searched from database inception until 14 February 2021 to identify relevant studies. Peer-reviewed research articles that reported the prevalence of PCOS, endometriosis, uterine fibroids, and adenomyosis in the Middle Eastern population were written in English or Arabic. The primary outcome was the estimated pooled prevalence of PCOS, endometriosis, uterine fibroids, and adenomyosis in the Middle Eastern populations. The secondary outcome was to assess the evidence in the data for the presence of heterogeneity, by conducting subtype-pooled analysis of prevalence estimates of the conditions. Total weighted prevalence was calculated via Freeman-Tukey arcsine transformation and heterogeneity through the I 2 statistic. Quality control was performed using GRADE criteria. Results: A total of 47 studies, 26 on PCOS, 12 on endometriosis, eight on uterine fibroids, and seven on adenomyosis, were included. The pooled prevalence of PCOS diagnosed according to the NIH criteria was 8.9% (95% CI: 6.5-11.7; prevalence range: 4.0-27.6%), with a higher prevalence from the Gulf Arab states (18.8%, 95% CI: 9.5-30.3; range: 12.1-27.6%). According to the Rotterdam criteria, the pooled prevalence of PCOS was 11.9% (95% CI: 7.1-17.7; range: 3.4-19.9%) with studies limited to the Persian and Levant regions. Endometriosis was diagnosed in 12.9% (95% CI: 4.2-25.4; range: 4.2-21.0%) of women undergoing laparoscopy, for any indication. Uterine fibroid and adenomyosis prevalence of women was 30.6% (95% CI: 24.9-36.7; range: 18.5-42.6%) and 30.8% (95% CI: 27.1-34.6, range: 25.6-37.7%), respectively. Heterogeneity was present between studies due to statistical and methodological inconsistencies between studies, and quality of evidence was low due to sample size and unrepresentative participant selection. Conclusion: This is the first review that has reported the prevalence of gynecological diseases in the Middle Eastern population, suggesting that gynecological morbidity is a public health concern. Due to the health disparities in women, further research is required to understand the relative roles of environmental and genetic factors in the region to serve as a benchmark for evaluation and comparative purposes with other populations.

Environmental toxicants, oxidative stress and health adversities: interventions of phytochemicals

OBJECTIVES

Oxidative stress is the most common factor mediating environmental chemical-induced health adversities. Recently, an exponential rise in the use of phytochemicals as an alternative therapeutics against oxidative stress-mediated diseases has been documented. Due to their free radical quenching property, plant-derived natural products have gained substantial attention as a therapeutic agent in environmental toxicology. The present review aimed to describe the therapeutic role of phytochemicals in mitigating environmental toxicant-mediated sub-cellular and organ toxicities via controlling cellular antioxidant response.

METHODS

The present review has covered the recently related studies, mainly focussing on the free radical scavenging role of phytochemicals in environmental toxicology.

KEY FINDINGS

In vitro and in vivo studies have reported that supplementation of antioxidant-rich compounds can ameliorate the toxicant-induced oxidative stress, thereby improving the health conditions. Improving the cellular antioxidant pool has been considered as a mode of action of phytochemicals. However, the other cellular targets of phytochemicals remain uncertain.

CONCLUSIONS

Knowing the therapeutic value of phytochemicals to mitigate the chemical-induced toxicity is an initial stage; mechanistic understanding needs to decipher for development as therapeutics. Moreover, examining the efficacy of phytochemicals against mixer toxicity and identifying the bioactive molecule are major challenges in the field.

DNA Methylation As an Epigenetic Mechanism in the Development of Multiple Sclerosis

The epigenetic mechanisms of gene expression regulation are a group of the key cellular and molecular pathways that lead to inherited alterations in genes' activity without changing their coding sequence. DNA methylation at the C5 position of cytosine in CpG dinucleotides is amongst the central epigenetic mechanisms. Currently, the number of studies that are devoted to the identification of methylation patterns specific to multiple sclerosis (MS), a severe chronic autoimmune disease of the central nervous system, is on a rapid rise. However, the issue of the contribution of DNA methylation to the development of the different clinical phenotypes of this highly heterogeneous disease has only begun to attract the attention of researchers. This review summarizes the data on the molecular mechanisms underlying DNA methylation and the MS risk factors that can affect the DNA methylation profile and, thereby, modulate the expression of the genes involved in the disease's pathogenesis. The focus of our attention is centered on the analysis of the published data on the differential methylation of DNA from various biological samples of MS patients obtained using both the candidate gene approach and high-throughput methods.

An Epigenetic Perspective on Lifestyle Medicine for Depression: Implications for Primary Care Practice

Depression is the most common presenting mental health disorder in primary care. It is also a major contributor to somatic complaints, worsening of chronic medical conditions, poor quality of life, and suicide. Current pharmacologic and psychotherapeutic approaches avert less than half of depression’s cumulative burden on society. However, there is a growing body of research describing both how maladaptive lifestyle choices contribute to the development and worsening of depression and how lifestyle-oriented medical interventions can reduce the incidence and severity of depression. This research, largely derived from an emerging field called epigenetics, elucidates the interactions between our lifestyle choices and those epigenetic factors which mediate our tendencies toward either health, or the onset, if not worsening of disease. The present review highlights how lifestyle choices involving diet, physical activity, sleep, social relationships, and stress influence epigenetic processes positively or negatively, and thereby play a significant role in determining whether one does or does not suffer from depression. The authors propose that medical training programs consider and adopt lifestyle medicine oriented instructional initiatives that will enable tomorrow’s primary care providers to more effectively identify and therapeutically intervene in the maladaptive choices contributing to their patients’ depression.

Genetic predisposition in type 2 diabetes: A promising approach toward a personalized management of diabetes

Diabetes mellitus, also known simply as diabetes, has been described as a chronic and complex endocrine metabolic disorder that is a leading cause of death across the globe. It is considered a key public health problem worldwide and one of four important non-communicable diseases prioritized for intervention through world health campaigns by various international foundations. Among its four categories, Type 2 diabetes (T2D) is the commonest form of diabetes accounting for over 90% of worldwide cases. Unlike monogenic inherited disorders that are passed on in a simple pattern, T2D is a multifactorial disease with a complex etiology, where a mixture of genetic and environmental factors are strong candidates for the development of the clinical condition and pathology. The genetic factors are believed to be key predisposing determinants in individual susceptibility to T2D. Therefore, identifying the predisposing genetic variants could be a crucial step in T2D management as it may ameliorate the clinical condition and preclude complications. Through an understanding the unique genetic and environmental factors that influence the development of this chronic disease individuals can benefit from personalized approaches to treatment. We searched the literature published in three electronic databases: PubMed, Scopus and ISI Web of Science for the current status of T2D and its associated genetic risk variants and discus promising approaches toward a personalized management of this chronic, non-communicable disorder.

Epigenetic Mechanisms in the Neurodevelopmental Theory of Depression

The genome (genes), epigenome, and environment work together from the earliest stages of human life to produce a phenotype of human health or disease. Epigenetic modifications, including among other things: DNA methylation, modifications of histones and chromatin structure, as well as functions of noncoding RNA, are coresponsible for specific patterns of gene expression. This refers also to mental disorders, including depressive disorders. Early childhood experiences accompanied by severe stressors (considered a risk factor for depression in adult life) are linked with changes in gene expression. They include genes involved in a response to stress (hypothalamic-pituitary-adrenal axis, HPA), associated with autonomic nervous system hyperactivity and with cortical, and subcortical processes of neuroplasticity and neurodegeneration. These are, among others: gene encoding glucocorticoid receptor, FK506 binding protein 5 gene (FKBP5), gene encoding arginine vasopressin and oestrogen receptor alpha, 5-hydroxy-tryptamine transporter gene (SLC6A4), and gene encoding brain-derived neurotrophic factor. How about personality? Can the experiences unique to every human being, the history of his or her development and gene-environment interactions, through epigenetic mechanisms, shape the features of our personality? Can we pass on these features to future generations? Hence, is the risk of depression inherent in our biological nature? Can we change our destiny?

Prophylactic efficacy of Boerhavia diffusa L. aqueous extract in toluene induced reproductive and developmental toxicity in Drosophila melanogaster

BACKGROUND

Environmental exposure to toxicants poses high risk to develop reproductive and developmental chronic toxicity in man. Toluene is one of the commonest industrial agents whose exposure is attributed with potential to induce reproductive and developmental toxicity. Since they contaminate the immediate environment of air and water to which humans are exposed, its containment is of great public health importance. Conventional treatment modalities fail owing to the difficulty to detect these highly volatile agents in environment and human body. The peril of such hazardous exposures is evident only when irreversible structural and functional damages have incurred. In such instances, prevention gains an upper hand when compared to therapeutic interventions. Several natural compounds derived from medicinal herbs possess potential to curb toxicities induced by such xenobiotic agents. Among them Boerhavia diffusa Linn. is a widely distributed and common herb attributed with antitoxic potential and capability for antioxidant defence. A study was performed on the prophylactic efficacy of aqueous extract of B. diffusa in curbing toluene induced developmental toxicity in Drosophila melanogaster.

METHODS

The study consisted of a preliminary phytochemical screening and HPTLC profiling of B. diffusa aqueous extract (BDAE). LC₅₀ of toluene was assessed and a sublethal dose of 200ppm was fixed for the study. Four doses of BDAE; 25, 50, 100 and 200mg/ml designated as Low dose, medium dose 1, medium dose 2 and high dose was used for the study. The parameters used for the study included the determination of larval period, pupal period, percentage of egg hatching, morphometric analysis of egg, larvae, pupae and adults, fertility, fecundity, lifespan and levels of antioxidant enzymes such as catalase, glutathione-S-transferase and superoxide dismutase.

RESULTS

The phytochemical and HPTLC characters were as per the pharmacopoeial standards. LC₅₀ of toluene was found to be 430ppm in this study. BDAE at medium dose 2 and high dose significantly prevented the deterioration of reproductive and developmental toxicity parameters of larval period, pupal period, percentage of egg hatching, morphometric characters of larva, pupa and adult, fertility, fecundity and lifespan in drosophila. Also the drug significantly elevated the levels of antioxidant enzymes.

CONCLUSION

Toluene exposure during lifetime is inevitable. B. diffusa, equipped with its rich active ingredients prevented toluene induced developmental and reproductive toxicity in Drosophila. This medicinal herb provides a ray of hope in preventing environmental toxin induced reproductive and developmental toxicity.

The utility of a system dynamics approach for understanding cumulative health risk from exposure to environmental hazards

The potential of system dynamics modeling to advance our understanding of cumulative risk in the service of optimal health is discussed. The focus is on exploring system dynamics modeling as a systems science methodology that can provide a framework for examining the complexity of real-world social and environmental exposures among populations-particularly those exposed to multiple disparate sources of risk. The discussion also examines how system dynamics modeling can engage a diverse body of key stakeholders throughout the modeling process, promoting the collective assessment of assumptions and systematic gathering of critical data. Though not a panacea, system dynamics modeling provides a promising methodology to complement traditional research methods in understanding cumulative health effects from exposure to multiple environmental and social stressors.

Hybrid Resiliency-Stressor Conceptual Framework for Informing Decision Support Tools and Addressing Environmental Injustice and Health Inequities

While structural factors may drive health inequities, certain health-promoting attributes of one's "place" known as salutogens may further moderate the cumulative impacts of exposures to socio-environmental stressors that behave as pathogens. Understanding the synergistic relationship between socio-environmental stressors and resilience factors is a critical component in reducing health inequities; however, the catalyst for this concept relies on community-engaged research approaches to ultimately strengthen resiliency and promote health. Furthermore, this concept has not been fully integrated into environmental justice and cumulative risk assessment screening tools designed to identify geospatial variability in environmental factors that may be associated with health inequities. As a result, we propose a hybrid resiliency-stressor conceptual framework to inform the development of environmental justice and cumulative risk assessment screening tools that can detect environmental inequities and opportunities for resilience in vulnerable populations. We explore the relationship between actual exposures to socio-environmental stressors, perceptions of stressors, and one's physiological and psychological stress response to environmental stimuli, which collectively may perpetuate health inequities by increasing allostatic load and initiating disease onset. This comprehensive framework expands the scope of existing screening tools to inform action-based solutions that rely on community-engaged research efforts to increase resiliency and promote positive health outcomes.

In Vivo genotoxicity of a commercial C.I. Disperse Red 1 dye

Color Index (C.I.) Disperse Red 1 (DR1) is a widely used textile azo dye found in rivers. As it may not be completely removed by conventional treatments, humans can be exposed through drinking water. Studies have supported in vitro toxicity and mutagenicity of commercial DR1. This study aimed to investigate the mutagenic and toxicogenomic effects of commercial DR1 in multiple tissues/organs of Swiss male mice. For that, animals were orally exposed to the dye (by gavage), at single doses of 0.0005, 0.005, 0.5, 50, or 500 mg/kg bw. The two lowest doses were equivalent to the ones found in two Brazilian rivers receiving influx of textile discharges. Cytotoxicity, micronucleated cell frequencies (for all doses tested), primary DNA damage (comet assay), and gene expression profiling of (0.0005 and 0.005 mg/kg of bw) were investigated 24 hr after animal exposure to commercial DR1. Data showed increased frequencies of micronucleated polychromatic erythrocytes in bone marrow cells after treatment with 0.5 and 50 mg/kg bw. At 0.005 mg/kg bw, commercial DR1 induced an increase of primary DNA damage in liver, but not in kidney cells. Additionally, upregulation of genes involved in the inflammatory process (IL1B) (0.0005 and 0.005 mg/kg bw) and cell-cycle control (CDKN1A) in liver cells, and apoptosis (BCL2 and BAX) in leukocytes (0.005 mg/kg bw) were also detected. In conclusion, the commercial DR1 was genotoxic (chromosome aberrations and primary DNA damage) and modulated gene expression in mice, and such effects were dependent on the doses and tissues analyzed. Environ. Mol. Mutagen. 59:822-828, 2018. © 2018 Wiley Periodicals, Inc.

Zebrafish models for personalized psychiatry: Insights from individual, strain and sex differences, and modeling gene x environment interactions

Currently becoming widely recognized, personalized psychiatry focuses on unique physiological and genetic profiles of patients to best tailor their therapy. However, the role of individual differences, as well as genetic and environmental factors, in human psychiatric disorders remains poorly understood. Animal experimental models are a valuable tool to improve our understanding of disease pathophysiology and its molecular mechanisms. Due to high reproduction capability, fully sequenced genome, easy gene editing, and high genetic and physiological homology with humans, zebrafish (Danio rerio) are emerging as a novel powerful model in biomedicine. Mounting evidence supports zebrafish as a useful model organism in CNS research. Robustly expressed in these fish, individual, strain, and sex differences shape their CNS responses to genetic, environmental, and pharmacological manipulations. Here, we discuss zebrafish as a promising complementary translational tool to further advance patient-centered personalized psychiatry.

Genotype combination contributes to psoriasis: An exhaustive algorithm perspective

Researchers have learned that nearly all conditions and diseases have a genetic component. With the benefit of technological advances, many single-nucleotide polymorphisms (SNPs) have been found to be associated with the risk of complex disorders by using genome wide association studies (GWASs). Disease-associated SNPs are sometimes shared by healthy controls and cannot clearly distinguish affected individuals from unaffected ones. The combined effects of multiple independent SNPs contribute to the disease process, but revealing the relationship between genotype and phenotype based on the combinations remains a great challenge. In this study, by considering the disease prevalence rate, we conducted an exhaustive process to identify whether a genotype combination pattern would have a decisive effect on complex disorders. Based on genotype data for 68 reported SNPs in 8,372 psoriasis patients and 8,510 healthy controls, we found that putative causal genotype combination patterns (CGCPs) were only present in psoriasis patients, not in healthy subjects. These results suggested that psoriasis might be contributed by combined genotypes, complementing the traditional modest susceptibility of a single variant in a single gene for a complex disease. This work is the first systematic study to analyze genotype combinations based on the reported susceptibility genes, considering each individual among the cases and controls from the Chinese population, and could potentially advance disease-gene mapping and precision medicine due to the causality relationship between the candidate CGCPs and complex diseases.

Pathway analysis of complex diseases for GWAS, extending to consider rare variants, multi-omics and interactions

BACKGROUND

Genome-wide association studies (GWAS) is a major method for studying the genetics of complex diseases. Finding all sequence variants to explain fully the aetiology of a disease is difficult because of their small effect sizes. To better explain disease mechanisms, pathway analysis is used to consolidate the effects of multiple variants, and hence increase the power of the study. While pathway analysis has previously been performed within GWAS only, it can now be extended to examining rare variants, other "-omics" and interaction data.

SCOPE OF REVIEW

1. Factors to consider in the choice of software for GWAS pathway analysis. 2. Examples of how pathway analysis is used to analyse rare variants, other "-omics" and interaction data.

MAJOR CONCLUSIONS

To choose appropriate software tools, factors for consideration include covariate compatibility, null hypothesis, one- or two-step analysis required, curation method of gene sets, size of pathways, and size of flanking regions to define gene boundaries. For rare variants, analysis performance depends on consistency between assumed and actual effect distribution of variants. Integration of other "-omics" data and interaction can better explain gene functions.

GENERAL SIGNIFICANCE

Pathway analysis methods will be more readily used for integration of multiple sources of data, and enable more accurate prediction of phenotypes.

The Socio-Exposome: Advancing Exposure Science and Environmental Justice in a Post-Genomic Era

We propose the socio-exposome as a conceptual framework for integrative environmental health research. Environmental scientists coined the term "exposome" with the goal of inventorying and quantifying environmental exposures as precisely as scientists measure genes and gene expression. To date, the exposome's proponents have not thoroughly engaged social scientific theoretical and methodological expertise, although the exclusion of sociological expertise risks molecularizing complex social phenomena and limiting the possibility of collective action to improve environmental conditions. As a corrective, and to demonstrate how "omic" technologies could be made more relevant to public health, our socio-exposome framework blends insights from sociological and public health research with insights from environmental justice scholarship and activism. We argue that environmental health science requires more comprehensive data on more and different kinds of environmental exposures, but also must consider the socio-political conditions and inequalities that allow hazards to continue unchecked. We propose a multidimensional framework oriented around three axes: individual, local, and global, and suggest some sociomarkers and data sources that could identify exposures at each level. This framework could also guide policy, by creating a predictive framework that helps communities understand the repercussions of corporate and regulatory practices for public health and social justice.

Epigenome: A Biomarker or Screening Tool to Evaluate Health Impact of Cumulative Exposure to Chemical and Non-Chemical Stressors

Current risk assessment practices and toxicity information are hard to utilize for assessing the health impact of combined or cumulative exposure to multiple chemical and non-chemical stressors encountered in the “real world” environment. Non-chemical stressors such as heat, radiation, noise, humidity, bacterial and viral agents, and social factors, like stress related to violence and socioeconomic position generally cannot be currently incorporated into the risk assessment paradigm. The Science and Decisions report released by the National Research Council (NRC) in 2009 emphasized the need to characterize the effects of multiple stressors, both chemical and non-chemical exposures. One impediment to developing information relating such non-chemical stressors to health effects and incorporating them into cumulative assessment has been the lack of analytical tools to easily and quantitatively monitor the cumulative exposure to combined effects of stressors over the life course.

Enacting the molecular imperative: How gene-environment interaction research links bodies and environments in the post-genomic age

Despite a proclaimed shift from 'nature versus nurture' to 'genes and environment' paradigms within biomedical and genomic science, capturing the environment and identifying gene-environment interactions (GEIs) has remained a challenge. What does 'the environment' mean in the post-genomic age? In this paper, we present qualitative data from a study of 33 principal investigators funded by the U.S. National Institutes of Health to conduct etiological research on three complex diseases (cancer, cardiovascular disease and diabetes). We examine their research practices and perspectives on the environment through the concept of molecularization: the social processes and transformations through which phenomena (diseases, identities, pollution, food, racial/ethnic classifications) are re-defined in terms of their molecular components and described in the language of molecular biology. We show how GEI researchers' expansive conceptualizations of the environment ultimately yield to the imperative to molecularize and personalize the environment. They seek to 'go into the body' and re-work the boundaries between bodies and environments. In the process, they create epistemic hinges to facilitate a turn from efforts to understand social and environmental exposures outside the body, to quantifying their effects inside the body. GEI researchers respond to these emergent imperatives with a mixture of excitement, ambivalence and frustration. We reflect on how GEI researchers struggle to make meaning of molecules in their work, and how they grapple with molecularization as a methodological and rhetorical imperative as well as a process transforming biomedical research practices.

Lack of association of intron 3 16 bp polymorphism of TP53 with breast cancer among Iranian-Azeri patients

BACKGROUND

p53 gene is a well-known tumor suppressor gene that has several polymorphisms in both its exons and introns. It has been suggested that intron 3 16 bp duplication polymorphism may affect the gene function resulting in reduction or suppression of p53 anti tumor activity. In most case control studies a duplicated allele has been noticeably more frequent in cases rather than controls but there are also conflicting results. The aim of this study was to assess the association of intron 3 16 bp duplication polymorphism of p53 with breast cancer risk among Iranian-Azeri population. We also analyzed the clinicopathological information of patients as an epidemiological description of breast cancer in the north-west of Iran.

MATERIALS AND METHODS

This case-control study was performed on 221 breast cancer patients and 170 controls. Genomic DNA was extracted from peripheral blood samples and tumor tissues. p53 PIN3 genotype was determined using electrophoresis of PCR products on 8% non-denaturing polyacrylamide gels and silver staining.

RESULTS

In the control and case groups, respectively, 62.9% and 61.1% had no 16 bp insertion (A1A1 genotype), 7.1% and 7.7% had insertion in both p53 alleles (A2A2) and 30% and 31.2% were heterozygous (A1A2). There was no significant difference between genotype frequencies as well as allelic frequencies in two case and control groups.

CONCLUSIONS

According to the result of the present study, the intron 3 16 bp duplication polymorphism of p53 could not be assessed as a marker of risk factor for predisposition to breast cancer in Azeri population. However, a high frequency of A2 allele (22.1%) in our population suggested that intron 3 16 bp duplication polymorphism may be a valuable marker for study in other cancers with well designed large groups.

The Navigation Guide systematic review methodology: a rigorous and transparent method for translating environmental health science into better health outcomes

BACKGROUND

Synthesizing what is known about the environmental drivers of health is instrumental to taking prevention-oriented action. Methods of research synthesis commonly used in environmental health lag behind systematic review methods developed in the clinical sciences over the past 20 years.

OBJECTIVES

We sought to develop a proof of concept of the "Navigation Guide," a systematic and transparent method of research synthesis in environmental health.

DISCUSSION

The Navigation Guide methodology builds on best practices in research synthesis in evidence-based medicine and environmental health. Key points of departure from current methods of expert-based narrative review prevalent in environmental health include a prespecified protocol, standardized and transparent documentation including expert judgment, a comprehensive search strategy, assessment of "risk of bias," and separation of the science from values and preferences. Key points of departure from evidence-based medicine include assigning a "moderate" quality rating to human observational studies and combining diverse evidence streams.

CONCLUSIONS

The Navigation Guide methodology is a systematic and rigorous approach to research synthesis that has been developed to reduce bias and maximize transparency in the evaluation of environmental health information. Although novel aspects of the method will require further development and validation, our findings demonstrated that improved methods of research synthesis under development at the National Toxicology Program and under consideration by the U.S. Environmental Protection Agency are fully achievable. The institutionalization of robust methods of systematic and transparent review would provide a concrete mechanism for linking science to timely action to prevent harm.

Association of TP53 PIN3 polymorphism with breast cancer in Moroccan population

TP53 is a tumor suppressor gene involved in cell cycle progression control, DNA damage repair, genomic stability, and apoptosis. Some polymorphisms in this gene have been associated with the development of a number of cancers including breast carcinoma. PIN3 Ins16bp polymorphism has been widely studied in different populations for an association with breast cancer risk. In most case-control studies, a duplicated allele has been more frequent in cases rather than controls but there are also inconsistent results. The present study aimed to assess the association of PIN3 Ins16bp polymorphism of p53 with breast cancer risk in Moroccan population. This case-control study was performed on 105 female patients with confirmed breast cancer and 114 healthy controls. The genotype frequency was 69.5 % (A1A1), 26.7 % (A1A2), and 3.8 % (A2A2) in patients and 68.4 % (A1A1), 24.6 % (A1A2), and 7 % (A2A2) in controls. No statistically significant association was observed between PIN3 Ins16bp polymorphism and breast cancer risk with odds ratio of 1.07 (confidence interval (CI) = 0.58-1.97, p = 0.83) for the heterozygous A1A2 and 0.53 (CI = 0.15-1.85, p = 0.32) for mutated homozygous A2A2.According to our preliminary genetic analysis, PIN3 Ins16pb polymorphism could not be assessed as a marker of risk factor for predisposition to breast cancer in Moroccan population. However, a high frequency of A2 allele (19.3 %) in our population suggested that PIN3 Ins16pb polymorphism may be a valuable marker for study in other cancers with larger groups.

A biobehavioral perspective on telomere length and the exposome

A major objective of biobehavioral research is defining the mechanisms that underlie linkages among behavior, biology, health, and disease. The genomic revolution has demonstrated the importance of studying the role of the environment in (epi)genetic mechanisms. The idea that interactions between environment and genetics influence health outcomes is a central concept of the exposome, a measure of environmental exposures throughout a lifetime. Research suggests that telomere length (TL) and biologic factors involved in telomere stability may provide an understanding of the effects of gene-environment interaction on disease risk. Telomeres, thus, have become important biomarkers for aging as well as for stress-related disease. However, incorporating telomeres into biobehavioral research requires consideration of several aspects of the exposome. Internal and external modifiable and nonmodifiable exposures have the potential to influence TL. Future research utilizing the concept of the exposome will provide meaningful findings related to exposure sources as well as dosage and duration across the life span that influence telomere biology and disease occurrence. Such findings can be translated into clinical practice and may provide a basis for personalized disease prevention and treatment approaches.

Risk communication and decision tools for children's health protection

Scientific discovery linking the environment to beneficial and adverse health children's health outcomes is rapidly expanding, leading scientists and health professionals to call for timely action to prevent harm and secure benefits. A robust method to synthesize what is known about the environmental drivers of health is a foundational step to making the science actionable by individuals and decision-makers. To meet this need, a methodology called the Navigation Guide was crafted by a collaboration of 22 clinical and environmental health scientists. The Navigation Guide proceeds from methods of research synthesis used in clinical settings but accounts for differences between environmental and clinical health sciences related to the evidence-base and decision-context. The methodology can be used to develop evidence profiles that provide simple, transparent summaries, such as practice guidelines or other evidence-based recommendations for prevention. Establishing proof-of-concept of the method is underway. Development of the Navigation Guide is extremely timely as it coincides with growing recognition of the need for updated methods in risk assessment. The costs in 2008 to the US healthcare system for treatment of childhood illnesses linked to toxic environmental exposures is conservatively estimated to be over $76 billion, and it is anticipated that US healthcare policy decisions will increasingly rely on systematic reviews of the evidence. The Navigation Guide is poised to provide a methodological bridge to link healthcare decision-making to efforts to reduce toxic environmental exposures. The institutionalization of the Navigation Guide would provide a concrete mechanism for linking science to action to protect children's health.

Factors affecting the 27K DNA methylation pattern in asthmatic and healthy children from locations with various environments

Gene expression levels are significantly regulated by DNA methylation. Differences in gene expression profiles in the populations from various locations with different environmental conditions were repeatedly observed. In this study we compare the methylation profiles in 200 blood samples of children (aged 7-15 years) with and without bronchial asthma from two regions in the Czech Republic with different levels of air pollution (a highly polluted Ostrava region and a control Prachatice region). Samples were collected in March 2010 when the mean concentrations of benzo[a]pyrene (B[a]P) measured by stationary monitoring were 10.1±2.4ng/m(3) in Ostrava Bartovice (5.6 times higher than in the control region). Significantly higher concentrations of other pollutants (benzene, NO2, respirable air particles and metals) were also found in Ostrava. We applied the Infinium Methylation Assay, using the Human Methylation 27K BeadChip with 27,578 CpG loci for identification of the DNA methylation pattern in studied groups. Results demonstrate a significant impact of different environmental conditions on the DNA methylation patterns of children from the two regions. We found 9916 CpG sites with significantly different methylation (beta value) between children from Ostrava vs. Prachatice from which 58 CpG sites had differences >10%. The methylation of all these 58 CpG sites was lower in children from polluted Ostrava, which indicates a higher gene expression in comparison with the control Prachatice region. We did not find a difference in DNA methylation patterns between children with and without bronchial asthma in individual locations, but patterns in both asthmatics and healthy children differed between Ostrava and Prachatice. Further, we show differences in DNA methylation pattern depending on gender and urinary cotinine levels. Other factors including length of gestation, birth weight and length of full breastfeeding are suggested as possible factors that can impact the DNA methylation pattern in future life.

Toxic environmental chemicals: the role of reproductive health professionals in preventing harmful exposures

Every pregnant woman in the United States is exposed to many and varied environmental chemicals. Rapidly accumulating scientific evidence documents that widespread exposure to environmental chemicals at levels that are encountered in daily life can impact reproductive and developmental health adversely. Preconception and prenatal exposure to environmental chemicals are of particular importance because they may have a profound and lasting impact on health across the life course. Thus, prevention of developmental exposures to environmental chemicals would benefit greatly from the active participation of reproductive health professionals in clinical and policy arenas.

Looking to the future: incorporating genomic information into disparities research to reduce measurement error and selection bias

OBJECTIVE

To extend recent conceptual and methodological advances in disparities research to include the incorporation of genomic information in analyses of racial/ethnic disparities in health care and health outcomes.

DATA SOURCES

Published literature on human genetic variation, the role of genetics in disease and response to treatment, and methodological developments in disparities research.

STUDY DESIGN

We present a conceptual framework for incorporating genomic information into the Institute of Medicine definition of racial/ethnic disparities in health care, identify key concepts used in disparities research that can be informed by genomics research, and illustrate the incorporation of genomic information into current methods using the example of HER-2 mutations guiding care for breast cancer.

PRINCIPAL FINDINGS

Genomic information has not yet been incorporated into disparities research, though it has direct relevance to concepts of race/ethnicity, health status, appropriate care, and socioeconomic status. The HER-2 example demonstrates how available genetic information can be incorporated into current disparities methods to reduce selection bias and measurement error. Advances in health information infrastructure may soon make standardized genetic information more available to health services researchers.

CONCLUSION

Genomic information can refine measurement of racial/ethnic disparities in health care and health outcomes and should be included wherever possible in disparities research.

Ethical concerns related to developing pharmacogenomic treatment strategies for addiction

Pharmacogenomics (PGx) research is poised to enable physicians to identify optimally effective treatments for individual substance abusers based on their genetic profiles. This paper addresses ethical issues related to PGx treatment strategies for addiction, focusing especially on the use of race variables in genomics research and ensuring equitable access to novel PGx treatments. Unless the field addresses the ethical challenges posed by these issues, PGx treatment innovations for addiction threaten to exacerbate already dramatic disparities in the burden of drug dependence for minority and other underserved populations.