Simple Familial And Sporadic Pituitary Adenoma Pituitary Adenoma AIP Gene Mutations

Pituitary gland is one of the most important endocrine glands of the human being. The prevalence rate of pituitary adenoma with clinical symptoms is as high as7.2/10000. It is defined as familial isolated pituitary adenoma (FIPA) when two or more family members are diagnosed as pituitary adenoma and no evidence of MEN I or CNC was confirmed. About22%of FIPA families harbor mutations in AIP gene, while it is2-3%in sporadic pituitary adenoma patients. AIP probably exerts its impact on pituitary carcinogenesis by making interaction with AhR, which is a ligand-inducible transcription factor. No data is available for AIP mutations in FIPA or sporadic pituitary adenoma patients in the Chinese population for the moment.Objectives:This study takes familial isolated pituitary adenoma kindreds and sporadic pituitary adenoma of the Chinese population as the objectives. By testing the mutations of the AIP gene, we studied the mutations of AIP gene in the pituitary adenoma patients in the Chinese population. As a consequence, the study could provide more evidence for the diagnosis and treatment of pituitary adenoma in the Chinese population, moreover, for the pituitary carcinogenesis.Materials and Methods:Genomic DNA was extracted from the leukocytes in the peripheral blood in7FIPA patients and their family members (the FIPA group) and50sporadic pituitary adenoma patients (the sporadic group). All6exons of the AIP gene were sequenced for mutations, and the potential mutations were validated by sequencing the normal population of100cases (the population validation group).Results:This study detected1missense mutation (c.215T>G, p. Y72S) in AIP gene in one of the50sporadic pituitary cases. But no nonsense, deletion, insertion, missense mutations were found in the7probands in3FIPA kindreds. The age of onset of pituitary adenoma in the FIPA group is significantly younger than that of the sporadic group (P=0.005). As for the acromegaly patients, the age of onset of pituitary adenoma in the FIPA group is also significantly younger than that of the sporadic group (P=0.003). Besides from those,3distinctive SNP loci were detected in the Chinese population as follows:C774T. C807Aå'ŒG1178C Conclusions:AIP mutation rate is fairly low in FIPA patients in the Chinese population. AIP gene is probably not a predisposing gene for FIPA patients in the Chinese population. The mutation rate of AIP gene in sporadic pituitary adenoma patient is about2%.