The Pediatric Inventory for Parents: Development of a short-form in fathers of children with type 1 diabetes (T1D).

BACKGROUND: The Pediatric Inventory for Parents (PIP) is a 42-item measure of paediatric parenting stress that results in 84 responses. Although this measure has been extensively validated, the number of items in the instrument may hinder clinical applicability. METHODS: The current study reports on the development of a short-form of the PIP using data from 344 fathers of children with type 1 diabetes. Recommendations for short-form development as well as item response theory (IRT) were used to construct a 13-item PIP Short-Form that results in 26 responses. RESULTS: The retained items were chosen to reflect the content domains of the original form of the PIP and demonstrated acceptable item fit under the partial credit model (PCM; Infit and Outfit indices closest to one and items with thresholds across the span of the latent trait). CONCLUSIONS: The PIP Short-Form may allow health care professionals to more feasibly assess paediatric parenting stress among parents of children with chronic health conditions. Future studies are needed to validate this new short-form.

Critical Issues in the Inclusion of Genetic and Epigenetic Information in Prevention and Intervention Trials.

Human genetic research in the past decade has generated a wealth of data from the genome-wide association scan era, much of which is catalogued and freely available. These data will typically test the relationship between a single nucleotide variant or polymorphism (SNP) and some outcome, disease, or trait. Ongoing investigations will yield a similar wealth of data regarding epigenetic phenomena. These data will typically test the relationship between DNA methylation at a single genomic location/region and some outcome. Most of these findings will be the result of cross-sectional investigations typically using ascertained cases and controls. Consequently, most methodological consideration focuses on methods appropriate for simple case-control comparisons. It is expected that a growing number of investigators with longitudinal experimental prevention or intervention cohorts will also measure genetic and epigenetic indicators as part of their investigations, harvesting the wealth of information generated by the genome-wide association study (GWAS) era to allow for targeted hypothesis testing in the next generation of prevention and intervention trials. Herein, we discuss appropriate quality control and statistical modelling of genetic, polygenic, and epigenetic measures in longitudinal models. We specifically discuss quality control, population stratification, genotype imputation, pathway approaches, and proper modelling of an interaction between a specific genetic variant and an environment variable (GxE interaction).

Informing Prevention and Intervention Policy Using Genetic Studies of Resistance.

The common paradigm for conceptualizing the influence of genetic and environmental factors on a particular disease relies on the concept of risk. Consequently, the bulk of etiologic, including genetic, work focuses on "risk" factors. These factors are aggregated at the high end of the distribution of liability to disease, the latent variable underlying the distribution of probability and severity of a disorder. However, liability has a symmetric but distinct aspect to risk, resistance to disorder. Resistance factors, aggregated at the low end of the liability distribution and supporting health and recovery, appear to be more promising for effective prevention and intervention. Herein, we discuss existing work on resistance factors, highlighting those with known genetic influences. We examine the utility of incorporating resistance genetics in prevention and intervention trials and compare the statistical power of a series of ascertainment schemes to develop a general framework for examining resistance outcomes in genetically informative designs. We find that an approach that samples individuals discordant on measured liability, a low-risk design, is the most feasible design and yields power equivalent to or higher than commonly used designs for detecting resistance genetic and environmental effects.

Parental Monitoring and Alcohol Use Across Adolescence in Black and White Girls: A Cross-Lagged Panel Mixture Model.

BACKGROUND: The link between parental monitoring and adolescent alcohol use is well established, but the directionality of this relationship is somewhat elusive. The literature suggests that parental engagement serves a protective function with respect to alcohol use, but that parental monitoring may also diminish in response to recurrent risk behavior. The lower rate of alcohol use despite evidence of lower levels of parental monitoring in Black versus White youth raises the question of for whom and under what conditions parental monitoring and alcohol use are associated. METHODS: Data were drawn from a community sample of 1,634 female adolescents (954 Black, 680 White) from 4 age cohorts, assessed annually in an accelerated longitudinal design. This study uses data spanning ages 12 to 17; parental monitoring and alcohol use were assessed via self-report, while demographic and adolescent psychosocial risk factors were derived from parent reports when the girls were age 12. An autoregressive cross-lagged panel mixture model was used to identify discrete patterns of parental monitoring and alcohol use associations across adolescence, and psychosocial factors that differentiate between them. RESULTS: Two discrete patterns of codeveloping alcohol use and parental monitoring emerged: one with stable bidirectional and autoregressive links (79%) and another differing from the majority profile in terms of the absence (alcohol use to parental monitoring) and direction (parental monitoring to alcohol use) of cross-construct influences (21%). Those in the minority profile were, at age 12, more likely to have received public assistance, resided in single-parent households, reached puberty, and manifest more severe conduct problems. CONCLUSIONS: Identifying subgroups of girls with distinct patterns of codeveloping alcohol use and parental monitoring is particularly relevant to the development and implementation of family-level interventions, both in terms of targeting those with known demographic risk factors, and tailoring programs to address behavioral correlates, such as conduct problems.

Dimensionality and Genetic Correlates of Problem Behavior in Low-Income African American Adolescents.

Researchers have long observed that problem behaviors tend to cluster together, particularly among adolescents. Epidemiological studies have suggested that this covariation is due, in part, to common genetic influences, and a number of plausible candidates have emerged as targets for investigation. To date, however, genetic association studies of these behaviors have focused mostly on unidimensional models of individual phenotypes within European American samples. Herein, we compared a series of confirmatory factor models to best characterize the structure of problem behavior (alcohol and marijuana use, sexual behavior, and disruptive behavior) within a representative community-based sample of 592 low-income African American adolescents (50.3% female), ages 13 to 18. We further explored the extent to which 3 genes previously implicated for their role in similar behavioral dimensions (CHRM2, GABRA2, and OPRM1) independently accounted for variance within factors specified in the best-fitting model. Supplementary analyses were conducted to derive comparative estimates for the predictive utility of these genes in more traditional unidimensional models. Findings provide initial evidence for a bifactor structure of problem behavior among African American adolescents and highlight novel genetic correlates of specific behavioral dimensions otherwise undetected in an orthogonal syndromal factor. Implications of this approach include increased precision in the assessment of problem behavior, with corresponding increases in the reliability and validity of identified genetic associations. As a corollary, the comparison of primary and supplementary association analyses illustrates the potential for overlooking and/or overinterpreting meaningful genetic effects when failing to adequately account for phenotypic complexity.

Associations Between Gestational Age at Birth and Alcohol Use in the Avon Longitudinal Study of Parents and Children.

BACKGROUND: The relationship between gestational age at birth (GA) and alcohol use measures in early adulthood was examined in a large U.K. community-based birth cohort (Avon Longitudinal Study of Parents and Children). METHODS: A series of linear and logistic regression models were used to test for main effects of a continuous measure of GA on a range of alcohol use measures, and moderation of these associations by sex. In addition, mediation analyses assessed the extent to which significant associations between GA and alcohol use operated indirectly, through influences of the parental environment and/or childhood measures of emotional and behavioral health (EBH). RESULTS: Earlier GA significantly predicted never drinking by age 18, but was not associated with other measures of alcohol use behavior among young adult drinkers (i.e., Self-Rating of the Effects of Alcohol, Alcohol Use Disorders Identification Test, or DSM-IV-TR Criteria for Alcohol Dependence). The association between earlier GA and never drinking by age 18 was moderated by sex, such that females born early were less likely to have ever had a drink by age 18. In the full sample, childhood measures of EBH were found to mediate the association between earlier GA and never drinking by age 18. This association was not mediated by parenting factors. CONCLUSIONS: Earlier GA is associated with never drinking alcohol in early adulthood, in females. Emotional and behavioral difficulties experienced in early childhood may mediate the relationship between earlier GA and never drinking by age 18.

Genes involved in stress response and alcohol use among high-risk African American youth.

BACKGROUND: Genetic and environmental factors influence substance use behaviors in youth. One of the known environmental risk factors is exposure to life stressors. The aim of this project is to study the interaction between NR3C1 and CRHBP, genes thought to be involved in stress pathways, exposure to stressful life events, and adolescent alcohol use/misuse. METHODS: The sample included 541 African American individuals (ages 13-18) from the Genes, Environment, and Neighborhood Initiative, a subset of the Mobile Youth Survey sample from whom DNA and more extensive phenotypic data were collected. Participants were selected from high-poverty neighborhoods in Mobile, Alabama, with potential exposure to a variety of extreme life stressors. RESULTS: A measure of stressful life events was significantly predictive of alcohol use/misuse. In addition, this association was significantly dependent upon the number of putative risk variants at rs1715749, a single-nucleotide polymorphism (SNP) in CRHBP (P ≤ .006). There was no significant interaction between NR3C1 and stressful life events with respect to alcohol use/misuse, after taking into account multiple testing. CONCLUSIONS: These findings suggest that CRHBP variants are potentially relevant for adolescent alcohol use/misuse among African American youth populations being reared within the context of stressful life events and warrant replication.

Testing for measured gene-environment interaction: problems with the use of cross-product terms and a regression model reparameterization solution.

The study of gene-environment interaction (G × E) has garnered widespread attention. The most common way to assess interaction effects is in a regression model with a G × E interaction term that is a product of the values specified for the genotypic (G) and environmental (E) variables. In this paper we discuss the circumstances under which interaction can be modeled as a product term and cases in which use of a product term is inappropriate and may lead to erroneous conclusions about the presence and nature of interaction effects. In the case of a binary coded genetic variant (as used in dominant and recessive models, or where the minor allele occurs so infrequently that it is not observed in the homozygous state), the regression coefficient corresponding to a significant interaction term reflects a slope difference between the two genotype categories and appropriately characterizes the statistical interaction between the genetic and environmental variables. However, when using a three-category polymorphic genotype, as is commonly done when modeling an additive effect, both false positive and false negative results can occur, and the nature of the interaction can be misrepresented. We present a reparameterized regression equation that accurately captures interaction effects without the constraints imposed by modeling interactions using a single cross-product term. In addition, we provide a series of recommendations for making conclusions about the presence of meaningful G × E interactions, which take into account the nature of the observed interactions and whether they map onto sensible genotypic models.

Childhood internalizing symptoms are negatively associated with early adolescent alcohol use.

BACKGROUND: The relationship between childhood internalizing problems and early adolescent alcohol use has been infrequently explored and remains unclear. METHODS: We employed growth mixture modeling of internalizing symptoms for a large, population-based sample of U.K. children (the Avon Longitudinal Study of Parents and Children Cohort) to identify trajectories of childhood internalizing symptoms from age 4 through age 11.5. We then examined the relationship between membership in each trajectory and alcohol use in early adolescence (reported at age 13.8). RESULTS: Overall, children experiencing elevated levels of internalizing symptoms were less likely to use alcohol in early adolescence. This finding held true across all internalizing trajectories; that is, those exhibiting increasing levels of internalizing symptoms over time, and those whose symptoms desisted over time, were both less likely to use alcohol than their peers who did not exhibit internalizing problems. CONCLUSIONS: We conclude that childhood internalizing symptoms, unlike adolescent symptoms, are negatively associated with early adolescent alcohol experimentation. Additional studies are warranted to follow up on our preliminary evidence that symptoms of phobia and separation anxiety drive this effect.

Genetic influences on alcohol use across stages of development: GABRA2 and longitudinal trajectories of drunkenness from adolescence to young adulthood.

Longitudinal analyses allow us to understand how genetic risk unfolds across development, in a way that is not possible with cross-sectional analyses of individuals at different ages. This has received little attention in genetic association analyses. In this study, we test for genetic effects of GABRA2, a gene previously associated with alcohol dependence, on trajectories of drunkenness from age 14 to 25. We use data from 1070 individuals who participated in the prospective sample of the Collaborative Study on the Genetics of Alcoholism, in order to better understand the unfolding of genetic risk across development. Piecewise linear growth models were fit to model the influence of genotype on rate of increase in drunkenness from early adolescence to young adulthood (14-18 years), the change in drunkenness during the transition to adulthood (18-19 years) and the rate of change in drunkenness across young adulthood (≥ 19 years). Variation in GABRA2 was associated with an increase in drunkenness that occurred at the transition between adolescence and adulthood. The genotypic effect was more pronounced in females. These analyses illustrate the importance of longitudinal data to characterize how genetic effects unfold across development. The findings suggest that transitions across important developmental periods may alter the relative importance of genetic effects on patterns of alcohol use. The findings also suggest the importance of considering gender when evaluating genetic effects on drinking patterns in males and females.

Fetal and maternal genes' influence on gestational age in a quantitative genetic analysis of 244,000 Swedish births.

Although there is increasing evidence that genetic factors influence gestational age, it is unclear to what extent this is due to fetal and/or maternal genes. In this study, we apply a novel analytical model to estimate genetic and environmental contributions to pregnancy history records obtained from 165,952 Swedish families consisting of offspring of twins, full siblings, and half-siblings (1987-2008). Results indicated that fetal genetic factors explained 13.1% (95% confidence interval (CI): 6.8, 19.4) of the variation in gestational age at delivery, while maternal genetic factors accounted for 20.6% (95% CI: 18.1, 23.2). The largest contribution to differences in the timing of birth were environmental factors, of which 10.1% (95% CI: 7.0, 13.2) was due to factors shared by births of the same mother, and 56.2% (95% CI: 53.0, 59.4) was pregnancy specific. Similar models fit to the same data dichotomized at clinically meaningful thresholds (e.g., preterm birth) resulted in less stable parameter estimates, but the collective results supported a model of homogeneous genetic and environmental effects across the range of gestational age. Since environmental factors explained most differences in the timing of birth, genetic studies may benefit from understanding the specific effect of fetal and maternal genes in the context of these yet-unidentified factors.

Adolescent alcohol use is predicted by childhood temperament factors before age 5, with mediation through personality and peers.

BACKGROUND: Very few studies chart developmental pathways from early childhood to adolescent alcohol-related outcomes. We test whether measures of temperament collected from mothers at multiple assessments from 6 months through 5 years predict alcohol-related outcomes in mid-adolescence, the developmental pathways that mediate these effects, and whether there are gender differences in pathways of risk. METHODS: Structural models were fit to longitudinal data from the Avon Longitudinal Study of Parents and Children, an epidemiological sample of pregnant women with delivery dates between April 1991 and December 1992, with children followed longitudinally. Temperamental characteristics were assessed at 6 time points from 6 to 69 months of age. Alcohol use and problems were assessed at age 15.5. Analyses here utilize data from 6,504 boys and 6,143 girls. RESULTS: Childhood temperament prior to age 5 predicted adolescent alcohol use and problems at age 15.5 years, even after controlling for socio-demographic factors and parental alcohol problems. In both boys and girls, 2 largely uncorrelated and distinct temperament styles-children who were rated as having consistent emotional and conduct difficulties through age 5, and children who were rated as consistently sociable through age 5-both showed elevated rates of alcohol problems at age 15.5, but via different mediational pathways. In both genders, the association between emotional and conduct difficulties and alcohol problems was mediated through reduced conscientiousness and lower emotional stability. The association between sociability and alcohol problems was mediated through increased extraversion and sensation-seeking for both genders. Boys also showed mediation for sociability and alcohol outcomes through friendship characteristics, and girls through lower conscientiousness and reduced emotional stability. CONCLUSIONS: Our findings support multiple pathways to alcohol consumption and problems in adolescence. Some of these pathways are shared in boys and girls, while other risk factors are more salient in one gender or the other.

How phenotype and developmental stage affect the genes we find: GABRA2 and impulsivity.

CONTEXT: The detection and replication of genes involved in psychiatric outcome has been notoriously difficult. Phenotypic measurement has been offered as one explanation, although most of this discussion has focused on problems with binary diagnoses. OBJECTIVE: This article focuses on two additional components of phenotypic measurement that deserve further consideration in evaluating genetic associations: (1) the measure used to reflect the outcome of interest, and (2) the developmental stage of the study population. We focus our discussion of these issues around the construct of impulsivity and externalizing disorders, and the association of these measures with a specific gene, GABRA2. DESIGN, SETTING, AND PARTICIPANTS: Data were analyzed from the Collaborative Study on the Genetics of Alcoholism Phase IV assessment of adolescents and young adults (ages 12-26; N = 2,128). MAIN OUTCOME MEASURES: Alcohol dependence, illicit drug dependence, childhood conduct disorder, and adult antisocial personality disorder symptoms were measured by psychiatric interview; Achenbach youth/adult self-report externalizing scale; Zuckerman Sensation-Seeking scale; Barratt Impulsivity scale; NEO extraversion and consciousness. RESULTS: GABRA2 was associated with subclinical levels of externalizing behavior as measured by the Achenbach in both the adolescent and young adult samples. Contrary to previous associations in adult samples, it was not associated with clinical-level DSM symptom counts of any externalizing disorders in these younger samples. There was also association with sensation-seeking and extraversion, but only in the adolescent sample. There was no association with the Barratt impulsivity scale or conscientiousness. CONCLUSIONS: Our results suggest that the pathway by which GABRA2 initially confers risk for eventual alcohol problems begins with a predisposition to sensation-seeking early in adolescence. The findings support the heterogeneous nature of impulsivity and demonstrate that both the measure used to assess a construct of interest and the age of the participants can have profound implications for the detection of genetic associations.

Mental Health in Mothers of Autistic Children with a Medical Home: The Potentially Mechanistic Roles of Coping and Social Support.

Mothers of autistic children often report poor mental health outcomes. One established risk factor for these outcomes is the child having a medical home. This study examined possible mediating variables (coping, social support) in this relationship in 988 mothers of autistic children from the 2017/2018 National Survey of Children's Health (NSCH). The results of the multiple mediation model suggest the relationship between having a medical home and maternal mental health is largely explained by indirect associations with coping and social support. These findings suggest that clinical interventions for coping and social support provided by the medical home for mothers of autistic children may improve maternal mental health outcomes over and above implementation of a medical home.

Study protocol to quantify the genetic architecture of sonographic cervical length and its relationship to spontaneous preterm birth.

INTRODUCTION: A short cervix (cervical length <25 mm) in the midtrimester (18-24 weeks) of pregnancy is a powerful predictor of spontaneous preterm delivery. Although the biological mechanisms of cervical change during pregnancy have been the subject of extensive investigation, little is known about whether genes influence the length of the cervix, or the extent to which genetic factors contribute to premature cervical shortening. Defining the genetic architecture of cervical length is foundational to understanding the aetiology of a short cervix and its contribution to an increased risk of spontaneous preterm delivery. METHODS/ANALYSIS: The proposed study is designed to characterise the genetic architecture of cervical length and its genetic relationship to gestational age at delivery in a large cohort of Black/African American women, who are at an increased risk of developing a short cervix and delivering preterm. Repeated measurements of cervical length will be modelled as a longitudinal growth curve, with parameters estimating the initial length of the cervix at the beginning of pregnancy, and its rate of change over time. Genome-wide complex trait analysis methods will be used to estimate the heritability of cervical length growth parameters and their bivariate genetic correlation with gestational age at delivery. Polygenic risk profiling will assess maternal genetic risk for developing a short cervix and subsequently delivering preterm and evaluate the role of cervical length in mediating the relationship between maternal genetic variation and gestational age at delivery. ETHICS/DISSEMINATION: The proposed analyses will be conducted using deidentified data from participants in an IRB-approved study of longitudinal cervical length who provided blood samples and written informed consent for their use in future genetic research. These analyses are preregistered with the Center for Open Science using the AsPredicted format and the results and genomic summary statistics will be published in a peer-reviewed journal.

CHRM2, parental monitoring, and adolescent externalizing behavior: evidence for gene-environment interaction.

Psychologists, with their long-standing tradition of studying mechanistic processes, can make important contributions to further characterizing the risk associated with genes identified as influencing risk for psychiatric disorders. We report one such effort with respect to CHRM2, which codes for the cholinergic muscarinic 2 receptor and was of interest originally for its association with alcohol dependence. We tested for association between CHRM2 and prospectively measured externalizing behavior in a longitudinal, community-based sample of adolescents, as well as for moderation of this association by parental monitoring. We found evidence for an interaction in which the association between the genotype and externalizing behavior was stronger in environments with lower parental monitoring. There was also suggestion of a crossover effect, in which the genotype associated with the highest levels of externalizing behavior under low parental monitoring had the lowest levels of externalizing behavior at the extreme high end of parental monitoring. The difficulties involved in distinguishing mechanisms of gene-environment interaction are discussed.

Differential susceptibility to adolescent externalizing trajectories: examining the interplay between CHRM2 and peer group antisocial behavior.

The present study characterized prototypical patterns of development in self-reported externalizing behavior, between 12 and 22 years of age, within a community sample of 452 genotyped individuals. A Caucasian subset (n = 378) was then examined to determine whether their probabilities of displaying discrete trajectories were differentially associated with CHRM2, a gene implicated in self-regulatory processes across a range of externalizing behaviors, and if affiliating with antisocial peers moderated these associations. Findings indicate that relative to a normative "lower risk" externalizing trajectory, likelihood of membership in two "higher risk" trajectories increased with each additional copy of the minor allelic variant at CHRM2, and that this association was exacerbated among those exposed to higher levels of peer group antisocial behavior.

Patterns of bi-directional relations across alcohol use, religiosity, and self-control in adolescent girls.

Examining predictors of alcohol use among adolescent girls is increasingly important to enhance prevention efforts, given that the gender gap in alcohol use is steadily closing. While both religiosity and self-control have been independently associated with decreased alcohol use, little research has explored 1) whether religiosity and self-control are reciprocally related and 2) whether the reciprocal association between these constructs may indicate different patterns in the development of alcohol use. As such, this study examined whether there are multiple patterns of reciprocal relationships across religiosity, self-control, and alcohol use among adolescent girls. Latent variable mixture modeling was combined with an autoregressive cross-lagged panel model to identify discrete, prototypical patterns of longitudinal associations (i.e., subgroups) across religiosity, self-control, and alcohol use among 2,122 girls ages 13-17. Psychosocial covariates (e.g., conduct problems) were examined as predictors of each subgroup. Two subgroups were identified. Self-control was associated with reduced alcohol use in both the majority (87.56% of the sample) and minority (12.44% of the sample) subgroups, but only the majority subgroup also demonstrated associations between religiosity, self-control, and alcohol use. Religiosity may predict lower alcohol use in a majority of adolescent girls but this association may not be present among all girls, suggesting that there is a qualitative difference in how religiosity is associated with self-control and alcohol use between subgroups. Results also suggest that higher levels of conduct problems may predict which girls are more likely to demonstrate associations between only self-control and alcohol use, and demonstrate no significant associations with religiosity.

MAOA-uVNTR and early physical discipline interact to influence delinquent behavior.

BACKGROUND: A functional polymorphism in the promoter region of the monoamine oxidizing gene monoamine oxidase A (MAOA) has been associated with behavioral sensitivity to adverse environmental conditions in multiple studies (e.g., Caspi et al. 2002; Kim-Cohen et al., 2006). The present study investigates the effects of genotype and early physical discipline on externalizing behavior. We expand on the current literature in our assessment of externalizing, incorporating information across multiple reporters and over a broad developmental time period, and in our understanding of environmental risk. METHOD: This study uses data from the Child Development Project, an ongoing longitudinal study following a community sample of children beginning at age 5. Physical discipline before age 6 was quantified using a subset of questions from the Conflict Tactics Scale (Straus, 1979). Externalizing behavior was assessed in the male, European-American sub-sample (N = 250) by parent, teacher, and self-report using Achenbach's Child Behavior Checklist, Teacher Report Form, and Youth Self-Report (Achenbach, 1991), at 17 time points from ages 6 to 22. Regression analyses tested the influence of genotype, physical discipline, and their interaction on externalizing behavior, and its subscales, delinquency and aggression. RESULTS: We found a significant interaction effect between genotype and physical discipline on levels of delinquent behavior. Similar trends were observed for aggression and overall externalizing behavior, although these did not reach statistical significance. Main effects of physical discipline held for all outcome variables, and no main effects held for genotype. CONCLUSION: The adverse consequences of physical discipline on forms of externalizing behavior are exacerbated by an underlying biological risk conferred by MAOA genotype.

Replicated umbilical cord blood DNA methylation loci associated with gestational age at birth.

DNA methylation is highly sensitive to in utero perturbations and has an established role in both embryonic development and regulation of gene expression. The foetal genetic component has been previously shown to contribute significantly to the timing of birth, yet little is known about the identity and behaviour of individual genes. The aim of this study was to test the extent genome-wide DNA methylation levels in umbilical cord blood were associated with gestational age at birth (GA). Findings were validated in an independent sample and evidence for the regulation of gene expression was evaluated for cis gene relationships in specimens with multi-omic data. Genome-wide DNA methylation, measured by the Illumina Infinium Human Methylation 450 K BeadChip, was associated with GA for 2,372 CpG probes (5% FDR) in both the Pregnancy, Race, Environment, Genes (PREG) and Newborn Epigenetic Study (NEST) cohorts. Significant probes mapped to 1,640 characterized genes and an association with nearby gene expression measures obtained by the Affymetrix HG-133A microarray was found for 11 genes. Differentially methylated positions were enriched for actively transcribed and enhancer chromatin states, were predominately located outside of CpG islands, and mapped to genes enriched for inflammation and innate immunity ontologies. In both PREG and NEST, the first principal component derived from these probes explained approximately one-half (58.1% and 47.8%, respectively) of the variation in GA. Gene pathways identified are consistent with the hypothesis of pathogen detection and response by the immune system to elicit premature labour as a consequence of unscheduled inflammation.