Low RET/PTC1 levels were detected in 26% (nine of 34) of papillary carcinomas with an expression pattern and proportion of FISH-positive cells similar to those of the thyroiditis.     ///    "real-time RT-PCR to quantify RET/PTC1, RET/PTC3, and c-RET transcripts. "    ///    Forty-seven percent (16 of 34) of papillary carcinomas and one oncocytic carcinoma expressed high RET/PTC1 mRNA levels.     ///    low-level RET/PTC was identified in 17% (five of 29) of thyroiditis cases by real-time RT-PCR and in an additional six of 11 real-time negative cases after increasing sensitivity with laser capture microdissection.     ///    "The objective of this study was to determine 1) whether RET/PTC occurs in nonneoplastic follicular cells of HT, and 2) its recombination rate in thyroid tumors. "    ///    Low-level RET/PTC recombination occurs in nonneoplastic follicular cells in HT and in a subset of papillary thyroid carcinomas.     ///    RET/PTC expression variability should be taken into account for the molecular diagnosis of thyroid lesions. 