Milk metagenome

Although previously considered sterile, breastmilk is now known to contain a complex community of bacteria. While their exact function is not known, it is speculated that milk microbiota help establish the infant's gut microbial community and influence development of the immune system. If this process is disrupted, the infant may develop a dysbiotic microbial community, causing predisposition to a range of chronic diseases such as allergy, asthma and obesity. Recent studies on human milk microbiota have confirmed the existence of a highly diverse bacterial community using culture-dependent and -independent techniques and suggest that its composition might be affected by local pathologies of the breast, mode of delivery, antibiotics, maternal health, and gestational age. However, these findings have not yet been reproduced in large-scale studies, and the determinants of milk microbiota are still mostly unknown.