Among them, one experienced a serious side effect (grade 4 thrombocytopenia), and the remaining nine had mild side effects, such as a decrease in WBC count and anorexia of grade 3 or less, suggesting that the combination of G‐CSF preparations20, 21 and supportive care22, 23, 24 could have allowed continuation of PEM therapy without dose reduction. The gene discussed is CSF3; the disease is Thrombocytopenia.