Aryl hydrocarbon receptor interacting protein variants in sporadic pituitary adenomas

Context: Proximal pathogenesis of pituitary tumors remains largely unclear. Recently, three heterozygous germline mutations were reported in the aryl hydrocarbon receptor interacting protein (AIP) gene in Finnish and Italian families with pituitary tumor predisposition and in Finnish patients harboring sporadic pituitary tumors. Objective: The objectives of this study were to examine the frequency of the three AIP germline mutations in U. S. patients harboring sporadic pituitary tumors and to correlate clinical features of pituitary tumors with these mutations, if they exist in these patients. Design: Genomic DNA was extracted from lymphoblastoid cell lines established from patients with sporadic pituitary tumors. Three segments of the AIP gene that contain the reported mutation sites for Q14X, IVS3-1G > A, and R304X were amplified by PCR and sequenced. Setting: The study was conducted in a private nonprofit academic medical center. Patients: The subjects were 66 consecutive patients (including 52 with acromegaly or prolactinoma) participating in a pituitary tumor database who consented to genetic study. Main Outcome Measure(s): The main outcome measure was the prevalence of these specific germline mutations in affected individuals. Results: AIP mutations were not detected in the 66 patients. A synonymous polymorphism was found in a single patient with acromegaly. Conclusions: The three specific AIP germline mutations do not play an important role in pathogenesis of sporadic pituitary tumors in U. S. patients.