medRxiv preprint doi: https://doi.org/10.1101/2020.12.16.20247700; this version posted February 22, 2021. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. It is made available under a CC-BY 4.0 International license . Vitamins D2 and D3 have overlapping but different effects on human gene expression revealed through analysis of blood transcriptomes in a randomised double-blind placebo-controlled food-fortification trial Louise R. Durrant,1, 2, Giselda Buccaa,b, 1,3, Andrew Heskethb, 1, Carla Möller-Leveta, Laura Tripkovica, Huihai Wua, Kathryn H. Harta, John C. Mathersc, Ruan M. Elliotta, Susan A. Lanham-Newa & Colin P. Smitha,b, 3* a Department of Nutritional Sciences, School of Biosciences and Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK b School of Pharmacy and Biomolecular Sciences, University of Brighton, Brighton, UK c Human Nutrition Research Centre, Population Health Sciences Institute, Newcastle University, UK 1 These authors contributed equally 2 Current address: Yakult UK Ltd., Anteros, Odyssey Business Park, West End Road, South Ruislip, HA4 6QQ; formerly known as Louise Wilson. 3 Current address: School of Pharmacy and Biomolecular Sciences, University of Brighton, Brighton, UK *For correspondence: Prof Colin P. Smith, School of Pharmacy and Biomolecular Sciences, University of Brighton, Huxley Building, Moulsecoomb, Brighton, BN2 4GJ, UK; Tel. +44 (0)1273 642048. Email:
[email protected] Key words: Vitamin D3, vitamin D2, 25-hydroxyvitamin D, human transcriptome, immunity, ethnic differences, Covid-19 Abstract For the first time, we report the influence of vitamin D2 and vitamin D3 on genome- wide gene expression in whole blood from healthy women representing two ethnic groups, white European and South Asian.