Biology subjects

Macisaac, J. L.

Publications and source records attributed to Macisaac, J. L..

3 recordsLinked to original sources

bioRxiv2026

Children's DNA Methylation and Family Dynamics in a Congo Basin Subsistence Community: Links with Parental Conflict and Fathers' Caregiving

Family environments may contribute to childrens long-term health through biological processes, including epigenetic regulation such as DNA methylation (DNAm). However, most studies in this area focus on Euro-American populations while also rarely including fathering data. The current study investigated childrens blood DNAm associations with positive (father caregiving) and negative (parental conflict) family dynamics in a smaller-scale subsistence society living in the Congo Basin rainforest. We measured DNAm from dried blood spots of 54 children (mean age=8.48 years) and conducted three epigenome-wide association studies aimed at discovering differential co-methylated regions (CMRs) associated with family dynamics. Via path models, we investigated the health implications and shared contribution of family factors of the identified CMRs. Differential DNAm associated with family dynamics was localized to genes related to stress, immunology, development, and aging, thus possibly linking to childrens physical health and were simultaneously connected to other family factors such as number of siblings. Our findings suggested similarities in biological embedding of family factors across socio-ecologically diverse contexts.

bioinformatics↗

bioRxiv2026

Exercise induces Skeletal Muscle Methylome and Transcriptome changes, regardless of Age and COPD

Skeletal muscle atrophy and deconditioning contribute to functional limitation and disability in COPD. While transcriptome and DNA methylation changes accompany exercise in healthy muscle, their interaction with COPD status and ageing, and integrative analyses of methylome-transcriptome responses have not been explored. We performed gene expression and DNA methylation profiling in skeletal muscle of sedentary volunteers with COPD, age-matched older adults, and younger healthy individuals, before and during (1,4 and 8 weeks) supervised aerobic exercise training and after four weeks of detraining. Exercise induced transcriptomic and DNA methylation changes, but these responses were unaffected by COPD status or age. Subsequent analysis focusing on temporal exercise effects independent of disease or age revealed differential transcriptomic changes across time points, a subset of which significantly associated with DNA methylome alterations. Transient transcriptomic changes not linked to DNA methylation were enriched for inflammatory and oxidative stress pathways, whereas persistent methylation-associated adaptations were related to immunomodulation and tissue remodelling. Together, this study provides insight into molecular mechanisms contributing to skeletal muscle adaptation to aerobic exercise training in sedentary individuals.

genomics↗

bioRxiv2021

Factors Driving DNA Methylation Variation in Human Blood

Epigenetic changes are required for normal development, yet the nature and respective contribution of factors that drive epigenetic variation in humans remain to be fully characterized. Here, we assessed how the blood DNA methylome of 884 adults is affected by DNA sequence variation, age, sex and 139 factors relating to life habits and immunity. Furthermore, we investigated whether these effects are mediated or not by changes in cellular composition, measured by deep immunophenotyping. We show that DNA methylation differs substantially between naive and memory T cells, supporting the need for adjustment on these cell-types. By doing so, we find that latent cytomegalovirus infection drives DNA methylation variation and provide further support that the increased dispersion of DNA methylation with aging is due to epigenetic drift. Finally, our results indicate that cellular composition and DNA sequence variation are the strongest predictors of DNA methylation, highlighting critical factors for medical epigenomics studies.

genomics↗