title: Ethnic and diet-related differences in the healthy infant microbiome.
abstract: The infant gut is rapidly colonized by microorganisms soon after birth, and the composition of the microbiota is dynamic in the first year of life. Although a stable microbiome may not be established until 1 to 3 years after birth, the infant gut microbiota appears to be an important predictor of health outcomes in later life.
  
  
  
  We obtained stool at one year of age from 173 white Caucasian and 182 South Asian infants from two Canadian birth cohorts to gain insight into how maternal and early infancy exposures influence the development of the gut microbiota. We investigated whether the infant gut microbiota differed by ethnicity (referring to groups of people who have certain racial, cultural, religious, or other traits in common) and by breastfeeding status, while accounting for variations in maternal and infant exposures (such as maternal antibiotic use, gestational diabetes, vegetarianism, infant milk diet, time of introduction of solid food, infant birth weight, and weight gain in the first year).
  
  
  
  We demonstrate that ethnicity and infant feeding practices independently influence the infant gut microbiome at 1 year, and that ethnic differences can be mapped to alpha diversity as well as a higher abundance of lactic acid bacteria in South Asians and a higher abundance of genera within the order Clostridiales in white Caucasians.
  
  
  
  The infant gut microbiome is influenced by ethnicity and breastfeeding in the first year of life. Ethnic differences in the gut microbiome may reflect maternal/infant dietary differences and whether these differences are associated with future cardiometabolic outcomes can only be determined after prospective follow-up.
authors.affiliation: Department of Medicine, McMaster University, Hamilton, ON, Canada. stearns@mcmaster.ca.|Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, ON, Canada. stearns@mcmaster.ca.
authors.forename: Jennifer C
authors.initials: JC
authors.lastname: Stearns
authors.affiliation: Department of Medicine, McMaster University, Hamilton, ON, Canada.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Zulyniak
authors.affiliation: Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, ON, Canada.
authors.forename: Russell J
authors.initials: RJ
authors.lastname: de Souza
authors.affiliation: Department of Medicine, McMaster University, Hamilton, ON, Canada.
authors.forename: Natalie C
authors.initials: NC
authors.lastname: Campbell
authors.affiliation: Department of Medicine, McMaster University, Hamilton, ON, Canada.|Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, ON, Canada.
authors.forename: Michelle
authors.initials: M
authors.lastname: Fontes
authors.affiliation: Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, ON, Canada.
authors.forename: Mateen
authors.initials: M
authors.lastname: Shaikh
authors.affiliation: Department of Medicine, McMaster University, Hamilton, ON, Canada.
authors.forename: Malcolm R
authors.initials: MR
authors.lastname: Sears
authors.affiliation: Department of Immunology, Faculty of Medicine, University of Manitoba, Winnipeg, Manitoba, Canada.
authors.forename: Allan B
authors.initials: AB
authors.lastname: Becker
authors.affiliation: Department of Pediatrics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Piushkumar J
authors.initials: PJ
authors.lastname: Mandhane
authors.affiliation: Hospital for Sick Children & Department of Paediatrics, University of Toronto, Toronto, ON, Canada.
authors.forename: Padmaja
authors.initials: P
authors.lastname: Subbarao
authors.affiliation: BC Children's Hospital and Child and Family Research Institute, Department of Paediatrics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Stuart E
authors.initials: SE
authors.lastname: Turvey
authors.affiliation: Department of Medicine, McMaster University, Hamilton, ON, Canada.
authors.forename: Milan
authors.initials: M
authors.lastname: Gupta
authors.affiliation: Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, ON, Canada.
authors.forename: Joseph
authors.initials: J
authors.lastname: Beyene
authors.affiliation: Department of Medicine, McMaster University, Hamilton, ON, Canada.|Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, ON, Canada.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Surette
authors.affiliation: Department of Medicine, McMaster University, Hamilton, ON, Canada.|Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, ON, Canada.|Population Health Research Institute, Hamilton Health Sciences and McMaster University, Hamilton, Ontario, Canada.
authors.forename: Sonia S
authors.initials: SS
authors.lastname: Anand
mesh_terms: D001459:Bangladesh / Q000208:ethnology; D001942:Breast Feeding; D002170:Canada; D004032:Diet / Q000208:ethnology*; D005060:Europe / Q000208:ethnology; D005243:Feces / Q000382:microbiology; D005260:Female; D000069196:Gastrointestinal Microbiome; D006801:Humans; D007194:India / Q000208:ethnology; D007223:Infant; D008297:Male; D010154:Pakistan / Q000208:ethnology; D013188:Sri Lanka / Q000208:ethnology; D044465:White People
keywords: Breastfeeding; Diet; Ethnicity; Infant gut microbiome