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Sucrose Thresholds and Genetic Polymorphisms of Sweet and Bitter Taste Receptor Genes in Children

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Sucrose Thresholds and Genetic Polymorphisms of Sweet and Bitter Taste Receptor Genes in Children University of Pennsylvania ScholarlyCommons Publicly Accessible Penn Dissertations 2015 Sucrose Thresholds and Genetic Polymorphisms of Sweet and Bitter Taste Receptor Genes in Children Paule Valery Joseph University of Pennsylvania, [email protected] Follow this and additional works at: https://repository.upenn.edu/edissertations Part of the Genetics Commons, Human and Clinical Nutrition Commons, and the Nursing Commons Recommended Citation Joseph, Paule Valery, "Sucrose Thresholds and Genetic Polymorphisms of Sweet and Bitter Taste Receptor Genes in Children" (2015). Publicly Accessible Penn Dissertations. 1793. https://repository.upenn.edu/edissertations/1793 This paper is posted at ScholarlyCommons. https://repository.upenn.edu/edissertations/1793 For more information, please contact [email protected]. Sucrose Thresholds and Genetic Polymorphisms of Sweet and Bitter Taste Receptor Genes in Children Abstract SUCROSE THRESHOLDS AND GENETIC POLYMORPHISMS OF SWEET AND BITTER TASTE RECEPTOR GENES IN CHILDREN Paule Valery Joseph Charlene Compher, PhD, RD Background: Many illnesses of modern society are due to poor food choices. Excess consumption of sugars has been associated with obesity and diabetes. Children, due to their basic biology, are more vulnerable than adults to overeat foods rich in sugars. Little research has focused on whether there are individual differences among children in their sensitivity to sweet taste and if so the biological correlates of such differences. Aims: The goal of this study was to determine whether variations in children’s sucrose detection thresholds relate to their age and sex, taste genotype, added sugar or caloric intake, temperament or food neophobia and adiposity. Methods: Sucrose detection thresholds in children age 7-14 years were tested individually using a validated two-alternative, forced-choice, paired-comparison tracking method. Genetic variants of taste receptor genes were assayed: TAS1R2, TAS1R3 and GNAT3 (sweet taste receptor genes; one variant each) and the bitter receptor gene TAS2R38 (three variants). Children (n=216) were measured for body weight and height. A subset of 96 children was measured for percent body fat, waist to height ratio and added sugar and kcal intake. Results: Mean sucrose threshold was 12.0 (SD 12.9), 0.23 to 153.8 mM. Girls were more sensitive than boys [t(214) = 2.0, p=0.047] and older children more sensitive than younger children [r(214) = -0.16, p = 0.016]. Variants in the bitter but not the sweet taste receptor genes were related to sucrose threshold and sugar intake; children with two bitter-sensitive alleles could detect sucrose at lower concentrations [F(2,165) = 4.55, p = 0.012; rs1726866]. Children with these variants also reported eating more added sugar (%kcals; [F(2, 62) = 3.64, p = 0.032]) than did children with less sensitive alleles. Sucrose detection thresholds predicted central adiposity [F(2, 59) = 6.1, p = 0.016), but not percent body fat [F(2, 58) = 1.4, p = 0.238]) when adjusted for added sugar intake, temperament, age, sex and negative reaction to foods. Conclusions: Differences in sweet taste sensitivity may affect childhood dietary sugar intake with long- term health consequences, including obesity. There may be a more complex interplay between the bitter and sweet taste systems during development than previously appreciated. Understanding taste related parameters as well as other dimensions that may affect food consumption might help in developing weight management to minimize childhood obesity risk. Degree Type Dissertation Degree Name Doctor of Philosophy (PhD) Graduate Group Nursing First Advisor Charlene W. Compher Second Advisor Danielle R. Reed Keywords Diet, Genetics, Obesity, Polymorphism, Sucrose, Thresholds Subject Categories Genetics | Human and Clinical Nutrition | Nursing | Nutrition This dissertation is available at ScholarlyCommons: https://repository.upenn.edu/edissertations/1793 SUCROSE THRESHOLDS AND GENETIC POLYMORPHISMS OF SWEET AND BITTER TASTE RECEPTOR GENES IN CHILDREN Paule Valery Joseph, MSN, CRNP, CTN-B A DISSERTATION in Nursing Presented to the Faculties of the University of Pennsylvania in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy 2015 Supervisor of Dissertation Co-Supervisor of Dissertation _________ __________________ ___________________________ Charlene W. Compher, PhD, RD, FADA Danielle R. Reed, PhD Professor of Nutrition Science Member, Monell Chemical Senses Center Graduate Group Chairperson ______ _________ __________ Connie Ulrich, PhD, RN, FAAN Associate Professor of Nursing; and Associate Professor of Bioethics, Department of Medical Ethics, School of Medicine Dissertation Committee Marilyn S. Sommers, PhD, RN, FAAN Lillian S. Brunner Professor of Medical-Surgical Nursing Danielle Reed, PhD Member, Monell Chemical Senses Center Julie Mennella, PhD Member, Monell Chemical Senses Center SUCROSE THRESHOLDS AND GENETIC POLYMORPHISMS OF SWEET AND BITTER TASTE RECEPTOR GENES IN CHILDREN COPYRIGHT© 2015 Paule Valery Joseph This work is licensed under the Creative Commons Attribution-NonCommercial- ShareAlike 3.0 License To view a copy of this license, visit http://creativecommons.org/licenses/by-ny-sa/2.0/ DEDICATION I dedicate my dissertation work to my family and my loving partner. “The best kind of people, are the ones that come into your life, and make you see the sun where you once saw clouds. The people that believe in you so much, you start to believe in you yourself. The people that love you simply for being you. The once in a lifetime kind of people.”-~Unknown iii ACKNOWLEDGMENTS I would like to first thank the members of my interdisciplinary dissertation committee—not only for their time and extreme patience, but also for their intellectual contributions to my development as a nurse scientist. I would like to acknowledge my dissertation chair and academic mentor, Dr. Charlene Compher, who supported my idea of choosing a study in genetics for my dissertation, for her unconditional time and support. Thank you to Dr. Danielle Reed for taking a chance with me despite my unconventional career trajectory, for her time and dedication to mentor me. Thank you for the Friday afternoon science discussions, they certainly allowed me to explore things through different lenses and more specially thank you for giving me the opportunity to develop my science in her laboratory. Thank you to Dr. Julie Mennella for all of her advice and the generous use of her dataset for this project. I am grateful she agreed to serve as a member of my dissertation committee, for challenging me and pushing my thinking. Also my gratitude to Dr. Marilyn Sommers for helping me think about methodological and disparity issues and for the many thought-provoking questions and ideas. Thank you for being a member of my dissertation committee. Without all of their guidance, persistence and constant sharing of their perils of wisdom this dissertation would have not been possible. I would like to express my appreciation to a number of readers who contributed their time during my studies Drs. Linda Hatfield, Bart de Jonghe, Joseph Libonati and Yvonne Paterson. iv My sincere regards to many people at Monell Chemical Senses Center, but a special token of gratitude to Anna Lysenko, Michael Marquis, Corrine Mansfield, Lauren Shaw, Loma Inamdar, Susana Finkbeiner, Daniel Hwang, Charles Arayata (CJ), Dr. Nuala Bobowski, Dr. Valentina Parma, Dr. Casey Trimmer and Dr. Katharine Prigge their expert technical assistance and friendship. My experience in the lab was greatly enhanced thanks to the support they provided. Specially thanks to Ms. Patricia J. Watson for her valuable editorial assistance. My utmost gratitude to people at Penn. Particularly to Jesse Chittams who provided insight and statistical expertise that greatly assisted my dissertation. Thank you to Dr. Sherry Morgan from the biomedical library for the innumerable times she provided help. I would also like to thank my very amazing PhD cohort and other doctoral students at Penn Nursing and other programs at Penn for their friendship, care and moral support. The PhD program can be very isolating and lonely. I have been blessed to find a tight- knit group of friends to commiserate with. I will always appreciate all they have done for me and the many prayers. Profound thanks to my hard working parents who have sacrificed their lives for my sister and I. My parents unconditionally and good examples have taught me to work hard for the things that I aspire to achieve and for instilling in me the importance of responsibility, endurance and education. They provided unconditional love and care. I certainly would not have made it this far without them. Thank you to my lovely sister, who has been my best friend and beacon of support during my PhD program. Also to the rest of my family with my warmest regards for believing in me and supporting me when v all I had was a dream to come to America. Finally, to my partner I could have not asked for a better companion. Thank you for being my best friend and my rock, your unconditional support and encouragement helped me when I needed it the most. Thanks for always listening and being my cheerleader. To all, I will always be grateful for your constant prayers, source of support and encouragement during the times of success and challenges. I am truly thankful for having each of you in my life. Above all, I owe it all to God Almighty for granting me the wisdom, health and strength to undertake
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