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Boden, J. M.

Publications and source records attributed to Boden, J. M..

5 recordsLinked to original sources

Hypomethylation in FASTKD1 detected in the association between in utero tobacco exposure and conduct problem in a New Zealand longitudinal study

Despite the known adverse effects of in utero tobacco exposure on offspring health, maternal tobacco use during pregnancy remains prevalent and is a major driver of health inequalities. One such health inequality is the development of conduct problem (CP) in exposed offspring which may be mediated by methylation changes that persist into adulthood. Here we apply a genome-wide approach to probe the association between maternal tobacco use during pregnancy and CP outcomes in exposed offspring. We examined maternal tobacco use during pregnancy (in utero exposure) in the Christchurch Health and Development Study, a longitudinal birth cohort studied for over 40 years. We then evaluated the interaction between methylation effects of in utero exposure and CP score. When modelling this interaction between in utero exposure and CP score we detected nominal DNA methylation differences, at FASTKD1 which has roles in early development. Our observations are consistent with DNA methylation mediating the development of CP following in utero tobacco exposure. In addition, we detected nominal significance in FRMDA4 and MYO1G between individuals exposed to tobacco in utero and those that were unexposed, however these did not reach significance after adjustment for multiple testing. However due to limited power in our analysis, further studies are needed to investigate the interaction between in utero tobacco exposure and high CP health outcomes.

genomics↗

Epigenetic signatures associated with the observed link between maternal tobacco use during pregnancy, and offspring conduct problems in childhood and adolescence

Maternal tobacco smoking during pregnancy is a large driver of health inequalities and a higher prevalence of conduct problem has been observed in exposed offspring. Further, maternal tobacco use during pregnancy can also alter offspring DNA methylation. However, currently, limited molecular evidence have been found to support this observation. Thus we aim to examine the association between maternal tobacco use in pregnancy and whether offspring Conduct problems is mediated by tobacco exposure-induced via DNA methylation differences. Understanding the etiology of the causal link will be crucial in the early identification and treatment of CP in children and adolescents. DNA was sourced from the Christchurch Health and Development Study, a longitudinal birth cohort studied for over 40 years in New Zealand. Bisulfite-based amplicon sequencing of 10 loci known to play a role in neurodevelopment, or with associations with CP phenotypes, was undertaken. We identified nominally significant differential DNA methylation at specific CpG sites in CYP1A1, ASH2L and MEF2C in individuals with Conduct problems who were exposed to tobacco in utero. We conclude that environmentally-induced DNA methylation differences could play a role in the observed link between maternal tobacco use during pregnancy and childhood/adolescent Conduct problems However, larger sample sizes are needed to produce an adequate amount of power to investigate this interaction further.

genomics↗

A validation of Illumina EPIC array system with bisulfite-based amplicon sequencing

The Illumina Infinium(R) MethylationEPIC BeadChip system (hereafter EPIC array) is considered to be the current gold standard detection method for assessing DNA methylation at the genome-wide level. EPIC arrays are used for hypothesis generation or pilot studies, the natural conclusion is to validate methylation candidates and expand these in a larger cohort, in a targeted manner. As such, an accurate smaller-scale, targeted technique, that generates data at the individual CpG level that is equivalent to the EPIC array, is needed. Here, we tested an alternative DNA methylation detection technique, known as bisulfite-based amplicon sequencing (BSAS), to determine its ability to validate CpG sites detected in EPIC array studies. BSAS was able to detect differential DNA methylation at CpG sites to a degree which correlates highly with the EPIC array system. However, BSAS correlated less well with EPIC array data when the magnitude of change via EPIC array was greater than 5%, suggesting that this lower specificity at larger differential methylation values is a consequence of PCR amplification that BSAS requires. However, our data suggests that BSAS does offer advantages that the EPIC array: BSAS amplifies a region of the genome (~500bp) around a CpG of interest, allowing analyses of other CpGs in the region that may not be present on the EPIC array, aiding discovery of novel CpG sites and differentially methylated regions of interest. We conclude that BSAS offers a valid investigative tool for specific regions of the genome that are currently not contained on the array system.

genomics↗

Genome-wide DNA methylation analysis of heavy cannabis use in a New Zealand longitudinal cohort

Cannabis use is of increasing public health interest globally. Here we examined the effect of cannabis use, with and without tobacco, on genome-wide DNA methylation in a longitudinal birth cohort (Christchurch Health and Development Study). We found the most differentially methylated sites in cannabis with tobacco users were in the AHRR and F2RL3 genes, replicating previous studies on the effects of tobacco. Cannabis-only users had no evidence of differential methylation in these genes, or at any other loci at the epigenomewide significance level (P<10-7). However, there were 521 sites differentially methylated at P<0.001 which were enriched for genes involved in cardiomyopathy and neuronal signalling. Further, the most differentially methylated loci were associated with genes with reported roles in brain function (e.g. TMEM190, MUC3L, CDC20 and SP9). We conclude that the effects of cannabis use on the mature human blood methylome differ from, and are less pronounced than, the effects of tobacco use, and that larger sample sizes are required to investigate this further.

genomics↗

The Anorexia Nervosa Genetics Initiative: Overview and Methods

BackgroundGenetic factors contribute to anorexia nervosa (AN); and the first genome-wide significant locus has been identified. We describe methods and procedures for the Anorexia Nervosa Genetics Initiative (ANGI), an international collaboration designed to rapidly recruit 13000 individuals with AN as well as ancestrally matched controls. We present sample characteristics and the utility of an online eating disorder diagnostic questionnaire suitable for large-scale genetic and population research.\n\nMethodsANGI recruited from the United States (US), Australia/New Zealand (ANZ), Sweden (SE), and Denmark (DK). Recruitment was via national registers (SE, DK); treatment centers (US, ANZ, SE, DK); and social and traditional media (US, ANZ, SE). All cases had a lifetime AN diagnosis based on DSM-IV or ICD-10 criteria (excluding amenorrhea). Recruited controls had no lifetime history of disordered eating behaviors. To assess the positive and negative predictive validity of the online eating disorder questionnaire (ED100K-v1), 109 women also completed the Structured Clinical Interview for DSM-IV (SCID), Module H.\n\nResultsBlood samples and clinical information were collected from 13,364 individuals with lifetime AN and from controls. Online diagnostic phenotyping was effective and efficient; the validity of the questionnaire was acceptable.\n\nConclusionsOur multipronged recruitment approach was highly effective for rapid recruitment and can be used as a model for efforts by other groups. High online presence of individuals with AN rendered the Internet/social media a remarkably effective recruitment tool in some countries. ANGI has substantially augmented Psychiatric Genomics Consortium AN sample collection. ANGI is a registered clinical trial: clinicaltrials.gov NCT01916538; https://clinicaltrials.gov/ct2/show/NCT01916538?cond=Anorexia+Nervosa&draw=1&rank=3.

genetics↗