Interestingly, the transcriptional regulator of pancreatic beta-cell function and maturity-onset diabetes of the young (MODY4) gene HNF4A was found to the most significant upstream regulator in the IPA analysis for both PPP (p-value = 0.003; z-score = 0.45) and OD (p-value = 0.0001; z-score = 0.98) (Figure 3). Here, HNF4A is linked to type 2 diabetes mellitus.