In thyroid cancer with BRAF gene mutations, the presence of promoter methylation in SMOC2, TSHR, TERT, SLC5A8, PLEKHS1, PTEN, DAPK, PDLIM4 and RSK4 genes would lead to poor prognosis of thyroid cancer (Fig. 3). The gene discussed is SLC5A8; the disease is thyroid cancer.