Profile of Human Milk Oligosaccharides and FUT2 Polymorphism of Mothers in Indonesia

Profile of Human Milk Oligosaccharides and FUT2 Polymorphism of Mothers in Indonesia: A Study on the Association Between Maternal Genotype-Phenotype Secretor Status and Short Chain Fatty Acid Profile Based on the Mother-Infant Genotype Pair

Human milk oligosaccharides (HMOs), the third most abundant constituent of breastmilk, are known to have beneficial effects on infant immunity. Maternal genetic polymorphisms cause HMO variability. The FUT2 gene determines the secretor status, whereas the FUT3 gene is responsible for the expression of Lewis fucosyltransferase. Therefore, breastmilk can be classified to four groups according to the variation. To date, this variability has not been investigated in Indonesia. This study aims to evaluate the association between FUT2 gene polymorphism and 2'-Fucosyllactose (2'-FL) secretor phenotype. In addition, infant FUT2 gene polymorphism and short chain fatty acid (SCFA) profile from stool samples are also analysed.

Eligible mother-infant pairs are explained about this study. Those willing to participate in this study are asked for written informed consent. Mothers are interviewed about their baseline characteristics, family pedigree, nutritional intake, and routine drug consumption. Infants are checked for their birth history. Both are measured for weight and height.

Four specimens are collected from the subjects:

1. Mother

   1. Breastmilk

      Breastmilk is expressed at 8-11 AM to avoid variability due to circadian rhythm. One breast is emptied, 30 mL of breastmilk is stored in a sterile container, and the rest is returned for feeding. Breastmilk is divided to five 2-mL cryovials and stored in a -80°C freezer. The remaining is stored in a -20°C freezer.

   2. Blood

   Blood samples (3 mL) are collected for DNA extraction.

2. Infant

   1. Buccal cells

      Buccal swab kits are used to obtain samples for DNA extraction.

   2. Stool

Stool specimens are collected at the age of four weeks in a sterile container and stored in a -80°C storage before short chain fatty acid profile analysis.

Inclusion Criteria:

• Mother

  1. Minimum of 18 years old
  2. With term infants aged 2-5 weeks
  3. Exclusively breastfeed
  4. Healthy condition
  5. Agree to participate and sign the informed consent

• Infant

  1. Infant with mother who fulfil the eligibility criteria

Exclusion Criteria:

• Mother

  1. Has a Caucasian ancestor in two generations above
  2. Infant has multiple congenital anomalies

• Infant

  1. Has ever received antibiotics