title: Seasonal effects on gene expression.
abstract: Many health conditions, ranging from psychiatric disorders to cardiovascular disease, display notable seasonal variation in severity and onset. In order to understand the molecular processes underlying this phenomenon, we have examined seasonal variation in the transcriptome of 606 healthy individuals. We show that 74 transcripts associated with a 12-month seasonal cycle were enriched for processes involved in DNA repair and binding. An additional 94 transcripts demonstrated significant seasonal variability that was largely influenced by blood cell count levels. These transcripts were enriched for immune function, protein production, and specific cellular markers for lymphocytes. Accordingly, cell counts for erythrocytes, platelets, neutrophils, monocytes, and CD19 cells demonstrated significant association with a 12-month seasonal cycle. These results demonstrate that seasonal variation is an important environmental regulator of gene expression and blood cell composition. Notable changes in leukocyte counts and genes involved in immune function indicate that immune cell physiology varies throughout the year in healthy individuals.
authors.affiliation: University of Queensland Diamantina Institute, The Translational Research Institute, Brisbane, Queensland 4102, Australia; The Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia.
authors.forename: Anita
authors.initials: A
authors.lastname: Goldinger
authors.affiliation: University of Queensland Diamantina Institute, The Translational Research Institute, Brisbane, Queensland 4102, Australia.
authors.forename: Konstantin
authors.initials: K
authors.lastname: Shakhbazov
authors.affiliation: The Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia; Queensland Institute of Medical Research, Herston, Brisbane, QLD 4006, Australia.
authors.forename: Anjali K
authors.initials: AK
authors.lastname: Henders
authors.affiliation: University of Queensland Diamantina Institute, The Translational Research Institute, Brisbane, Queensland 4102, Australia; The Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia; Queensland Institute of Medical Research, Herston, Brisbane, QLD 4006, Australia.
authors.forename: Allan F
authors.initials: AF
authors.lastname: McRae
authors.affiliation: Queensland Institute of Medical Research, Herston, Brisbane, QLD 4006, Australia.
authors.forename: Grant W
authors.initials: GW
authors.lastname: Montgomery
authors.affiliation: The Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia.
authors.forename: Joseph E
authors.initials: JE
authors.lastname: Powell
mesh_terms: D006801:Humans; D007958:Leukocyte Count; D009000:Monocytes / Q000378:metabolism; D009504:Neutrophils / Q000378:metabolism; D012621:Seasons; D059467:Transcriptome / Q000235:genetics*