A 50-year-old man comes to the physician for a 12-hour history of shooting groin pain. Non-contrast CT of the abdomen confirms the diagnosis. He had a similar episode occur 1 year ago. Serum studies show a calcium of 12.1 mg/dL. A mutation in which of the following genes is the most likely explanation for these findings?
BRAF
EGFR
KRAS
MEN1
MLH1
TSC1