Figure 2.

Principal components analysis of human milk oligosaccharides (HMO) profiles. The HMO profiles in samples collected at 3-mo of lactation were determined using HLPC chip/time-of-flight MS and identified compared with annotated HMO libraries (57, 58). HMO profiles were compared using principal components analysis, which identified 3 clusters that primarily separated based on the content of 2 predominant HMO, 2′-fucosyllactose and lacto-N-tetraose. The 2′-fucosyllactose content increases and the lacto-N-tetraose content decreases from left to right. We conclude that genetic variation in secretor status (61) exists in the mothers enrolled in our study, which will facilitate establishing associations between milk HMO and infant microbiota.