Multiple endocrine neoplasia type 2（MEN2） are mainly characterized by medullary thyroid carcinoma, adrenal pheochromocytoma and primary hyperparathyroidism. The RET gene is a responsible gene for MEN2. RET gene analysis is helpful in confirming the diagnosis of MEN2, and is shown as grade A in clinical practice guideline for thyroid carcinomas in Japan. Since 2008, we have performed RET gene analysis as an advanced technology approved by the Japanese Ministry of Health, Labor and Welfare. And in 2009, we started to accept the analysis requested by another institution involved in MEN consortium group. The current problem of RET gene analysis is the difference in description of analysis report between each institutions. Therefore, it is difficult to interpret analysis data of the report and it is potentially confusing. A person responsible for the analysis tries to contrive ways to make easy-tounderstand report to prevent such problems. To that end, it is necessary to advance the knowledge about RET gene and MEN2, and think carefully if the commonlyused genetic terms get accepted in clinical sites. We aim to provide a higher-quality feedback in gene analysis.