Identification of the thyroid genes whose expressions are altered by neonatal irradiation in rats

Childhood radiation is a risk factor for thyroid cancer, which became well-known after the Chornobyl nuclear plant accident, where childhood thyroid cancer cases significantly increased afterward. The mechanisms of thyroid cancer susceptibility to radiation exposure at young ages, however, have not yet been understood. Our previous investigations demonstrated that neonatal exposure to X-rays induced long-term mRNA expression changes in the thyroid cancer-related marker genes in rats. Then, we searched for the genes whose expressions were altered by neonatal radiation exposure in male Wistar rats exposed to X-rays. Male Wistar rats at 1 week and 4 months old were subjected to cervical X-irradiation at 4 Gy. After 8 weeks, total RNAs were extracted from the thyroid and applied to RNA-seq analysis to identify the genes that only neonatal irradiation alters the mRNA expressions.