Preferential induction of RET/PTC1 rearrangement by X-ray irradiation..     ///    "High frequencies of RET/PTC rearrangements have been observed in radiation-associated PTC, such as those appearing post-Chernobyl or post-radiotherapy, but the rearrangement types differ between these two populations. "    ///    "In human normal thyroid tissues transplanted in scid mice, the RET/PTC1 rearrangement was predominantly detected throughout the observation period (up to 60 days) after X-ray exposure of 50 Gy. "    ///    We investigated whether a specific type of RET/PTC rearrangement was induced by X-rays in vivo and in vitro.     ///    These results suggest that the preferential induction of the RET/PTC1 rearrangement may play an important role in the early steps of thyroid carcinogenesis induced by acute X-irradiation..     ///    "The RET/PTC1 rearrangement was preferentially induced in a dose-dependent manner by X-rays within a high dose range (10, 50 and 100 Gy) in four cell lines. "    ///    "RET/PTC1, -2 and -3 are known to be the three major forms. "