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bioRxiv · 10.1101/185629

Genome-Wide Association Studies Identify 15 Genetic Markers Associated with Marmite Taste Preference

Abstract

Marmite is a popular food eaten around the world, to which individuals have commonly considered themselves either \"lovers\" or \"haters\". We aimed to determine whether this food preference has a genetic basis.Weperformed a genome-wide association study (GWAS) for Marmite taste preference using genotype and questionnaire data froma cohort of 261 healthy adults. We found 1 single nucleotide polymorphism (SNP) associated with Marmite taste preferencethat reached genome-wide significance (p<5x10-8) in our GWAS analyses. We found another 4 SNPsassociated with Marmite taste preference that reached genome-wide significance (p<5x10-8) in at leastoneGWAS and/or for at least one phenotype analysed. Moreover, we identified 10 additional SNPs potentially associated with Marmite taste preference through candidate gene analysis. Our results indicate that there is a genetic basis to Marmite taste preference and we have identified 15 genetic markers for this trait. Overall, we conclude that Marmite tastepreference is a complex human trait influenced by multiple genetic markers, as well as the environment.\n\nSummary of Main Results O_TEXTBOXO_LIMarmite taste preference is a complex human trait with many factors influencing whether an individual loves or hates Marmite.\nC_LIO_LIThe relative contribution of genetics versus environment (ie. heritability) for Marmite taste preference is unknown.\nC_LIO_LIThe genetic contribution to Marmite taste preference involves multiple genetic markers each contributing a small amount (ie. the trait is polygenic). There is not one single Marmite gene with a large contribution like in thecase of the TAS2R38gene and bitter taste perception.\nC_LIO_LIWe have found a total of 15 SNPs associated with Marmite taste preference: 5 SNPs by a genetic-association screen atgenome-wide significance, and 10 SNPs by a candidate gene approach at nominal significance.\nC_LIO_LIWe did not find an association between the TAS2R38bitter taste receptor gene and Marmite taste preference.\nC_LIO_LIIt is important to independently replicate the findings of this study in order to validate these genetic markers and get a more accurate idea of their true effect on Marmite taste preference.\nC_LI\n\nC_TEXTBOX

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Roos, T., Kulemin, N., Ahmetov, I., Lasarow, A., Grimaldi, K.. 2017-09-07. Genome-Wide Association Studies Identify 15 Genetic Markers Associated with Marmite Taste Preference. https://doi.org/10.1101/185629

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