From the KEGG database, the MAPK signalling pathway comprises of 267 genes, which included a list of 31 genes (ATF2, CHUK, DDIT3, DUSP4, DUSP5, DUSP6, DUSP8, FGF13, FGFR2, FGFR4, FLNA, FOS, GADD45G, HRAS, IKBKB, IL1R1, MAP2K4, MAP2K6, MAP3K8, MAP4K3, MAPK9, MAPKAPK5, MAX, PAK2, PPM1B, PPP3R1, RAPGEF2, RASA1, RPS6KA3, RPS6KA4 and SOS1) which are present in either or both of obesity-associated tGSS and the IGF1 pathway tGSS (Table 2). This evidence concerns the gene PAK2 and obesity due to melanocortin 4 receptor deficiency.