Variant Tyr 394Ser in the GCM2 Gene Is Rare in a Cohort of Ashkenazi Jews With Primary Hyperparathyroidism

CONTEXT: Various genes have been associated with familial and sporadic primary hyperparathyroidism (PHPT), including activating mutations of the glial cells missing transcription factor 2 (GCM2) gene. OBJECTIVE: The aim of this study was to assess the prevalence of the GCM2 p.Tyr394Ser variant in the Jerusalem Ashkenazi Jewish (AJ) population with PHPT, and to conclude whether routine genetic testing is justified. METHODS: The blood of 40 self-reported AJ patients with PHPT and 200 AJ controls was tested for the GCM2 p.Tyr394Ser variant. Demographic and medical information was extracted from the patients’ charts and evaluated accordingly. RESULTS: Two (5%) PHPT patients and 3 (1.5%) controls were heterozygotes for the tested variant. Our patients were mostly (87.5%) sporadic cases. One of the heterozygote patients had familial PHPT; the other had 2 parathyroid adenomas, and the levels of his blood and urinary calcium were extremely high. CONCLUSION: Our results suggest that in AJ patients with sporadic, single-gland PHPT, the likelihood of the tested variant is low and genetic testing should be limited to those with familial PHPT or multiglandular disease.