Figure 6. Methionine and metabolic variation in human subjects.

a.) Measurement of serum methionine and clinical and dietary variables in human subjects. b.) (left) Hierarchical clustering of the distance matrix diet variables. (right) k-means clustering of subjects and diet variables (N=24). c.) Absolute concentrations of amino acids in fasting serum in 38 human subjects. d.) Coefficients of variation of amino acids in fasting serum. e. Correlation of methionine in the serum with methylated serum metabolites, N,N,N- trimethyllysine and sarcosine.f.) Correlation of methionine concentrations with dietary variables obtained from habitual diet records. g.) Correlation of methionine concentrations with fasting serum metabolite levels.