**Figure 1.** **Total IgG glycan levels in five different populations.** Relationship between age and derived glycan trait (**A**). Plots describe associations between each of the five glycan traits and chronological age of participant. Blue and red curves represent fitted linear regression models. The shaded region is the 95 % confidence interval on the fitted values. Differences in total IgG glycosylation between participants from five different populations (**B**). Each box represents interquartile range (25^{th} to 75^{th} percentiles). Lines inside the boxes represent the median values, while lines outside the boxes represent the 10^{th} and 90^{th} percentiles. Dots indicate outliers.