J Neurogastroenterol Motil 2022; 28(2): 334-334  https://doi.org/10.5056/jnm22007
Sexual Dimorphism in the Gut Microbiome: Microgenderome or Microsexome? Author’s Reply
Nayoung Kim1,2
1Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, Gyeonggi-do, Korea; and 2Department of Internal Medicine and Liver Research Institute, Seoul National University College of Medicine, Seoul, Korea
Received: January 16, 2022; Revised: January 21, 2022; Accepted: January 21, 2022; Published online: April 30, 2022
© The Korean Society of Neurogastroenterology and Motility. All rights reserved.

cc This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
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TO THE EDITOR: Basically I agree with the authors of “Sexual dimorphism in the gut microbiome: microgenderome or microsexome?”1, which is a letter to the editor regarding the review article.2 Estrogen and androgens, the most widely known sex hormones, influence the gut microbiome, which in turn influences the metabolism of estrogen and androgens. These bidirectional interactions between the microbiota, hormones, immunity, and disease susceptibility has begun to be described as “microgenderome” mainly in human.3-6 Beta-glucuronidase of the gut microbiome converts conjugated estrogens to their deconjugated forms and this active deconjugated estrogen enters the enterohepatic circulation and act on estrogen receptor α and estrogen receptor β in the reproductive organs, muscle, nervous system, and vasculature; this applies to non-ovarian estrogen in men and postmenopausal women, but not ovarian estrogen in pre-menopausal women.3 However, as sex refers to biological characteristics related to hormones and genetics, and gender refers to sociocultural attitudes, behaviors, and identities, the term “microgenderome” may not be entirely accurate.1,6

Actually some authors indicate that the effect of “gender” on the gut microbiome is very minor in comparison to “sex.”7 However, it is true that the factors that influence the composition of the gut microbiome are diet, ethnicity, antibiotics, stress, psychological factors, maternal health during pregnancy, the method of birth (ie, vaginal birth versus cesarean section), environmental factors, and exercise, which are mainly related with “gender.” Considering national and international reports8,9 that women tend to prefer fruits and vegetables more than men, the contribution of “gender” differences to the gut microbiome is definite. In addition, stress susceptibility in pregnant women impairs vaginal immune activity and reduces the number of Lactobacillus, a component of the vaginal flora. However, it is true that “gender” term was made when it became clear that sex was not able to explain the biological difference between males and females is not the same in variable ethnicities and countries. That’s why the meaning of “gender” could be vague and inconsistent. Furthermore, the interrelationship of “sex” and “gender” is intimate that sometimes it is difficult to separate “gender” from “sex.” Taken together “micro-sex/genderome” may be better than either “microgenderome” or “microsexome.”

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References
  1. Mulak A, Larauche M, Taché Y. Sexual dimorphism in the gut microbiome: microgenderome or microsexome? J Neurogastroenterol Motil 2022;28:332-333.
    Pubmed CrossRef
  2. Yoon K, Kim N. Roles of sex hormones and gender in the gut microbiota. J Neurogastroenterol Motil 2021;27:314-325.
    Pubmed KoreaMed CrossRef
  3. Kwa M, Plottel CS, Blaser MJ, Adams S. The intestinal microbiome and estrogen receptor-positive female breast cancer. J Natl Cancer Inst 2016;108:djw029.
    Pubmed KoreaMed CrossRef
  4. Flak MB, Neves JF, Blumberg RS. Immunology. Welcome to the microgenderome. Science 2013;339:1044-1045.
    Pubmed KoreaMed CrossRef
  5. Wallis A, Butt H, Ball M, Lewis DP, Bruck D. Support for the microgenderome invites enquiry into sex differences. Gut Microbes 2017;8:46-52.
    Pubmed KoreaMed CrossRef
  6. Vemuri R, Sylvia KE, Klein SL, et al. The microgenderome revealed: sex differences in bidirectional interactions between the microbiota, hormones, immunity and disease susceptibility. Semin Immunopathol 2019;41:265-275.
    Pubmed KoreaMed CrossRef
  7. Kim YS, Unno T, Kim BY, Park MS. Sex differences in gut microbiota. World J Mens Health 2020;38:48-60.
    Pubmed KoreaMed CrossRef
  8. Lee HS, Cho YH, Park J, Shin HR, Sung MK. Dietary intake of phytonutrients in relation to fruit and vegetable consumption in Korea. J Acad Nutr Diet 2013;113:1194-1197.
    Pubmed CrossRef
  9. Regu GM, Kim H, Kim YJ, et al. Association between dietary carotenoid intake and bone mineral density in Korean adults aged 30-75 years using data from the fourth and fifth Korean national health and nutrition examination surveys (2008-2011). Nutrients 2017;9:1025.
    Pubmed KoreaMed CrossRef


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