Abstract
The DNA from a pituitary adenoma of a patient with multiple endocrine neoplasia (MEN) type 1 was analyzed to detect a point mutation of the Gsα gene (gsp) by the PCR direct-sequencing method. The patient had galactorrhea, amenorrhea and acromegalic features. Hormonal examination revealed high serum levels of PRL and GH. The tumor was histologically diagnosed as a mixed GH cell-PRL cell adenoma in which GH and PRL were produced by different cells. Sequence analysis of the DNAs extracted from paraffin sections of pituitary, parathyroid, and pancreas tumors demonstrated the substitution of thymidine for cytidine in codon 201 of the Gsα gene that resulted in replacement of arginine (CGT) with cystein (TGT) only in the pituitary adenoma, but not in the parathyroid and pancreas tumors. These results suggest that a pituitary specific point mutational activation of the Gsa gene may be involved in the development of the pituitary adenoma in this patient.
