However, in multifocal MEN1-gastrinomas, with Zollinger–Ellison syndrome, it has been described that LOH at 11q13 region can be found in less than 50% of patients, and within the same patient different tumoral foci frequently exhibited different patterns of LOH, ranging from LOH limited only to 11q13 to loss of the whole chromosome or no LOH, suggesting that each focus of gastrinoma may arise by an independent second hit (21). The gene discussed is MEN1; the disease is gastrin-producing neuroendocrine tumor.