Choreographed progression of gut bacteria

The population of bacteria in babies' gastrointestinal tracts may depend more on their biological makeup and gestational age at birth than on environmental factors.

This is because bacterial communities assemble in a pre-determined order scientists have discovered occurs as an orderly, choreographed progression.

The scientists at The Genome Institute at Washington University School of Medicine used DNA sequencing to tally the bacterial populations in 922 stool samples from 58 premature infants ranging from 23-33 weeks in gestational age and weighing