New pathogenic variants in ARMC5 gene in a series of Italian patients affected by primary bilateral macronodular adrenocortical hyperplasia (PBMAH)

Background: To perform genetic screening for ARMC5 gene germline pathogenic variants in patients with primary bilateral macronodular adrenal hyperplasia (PBMAH). Subjects and Methods: In a group of 10 PBMAH patients, we performed complete sequencing of the coding region of the ARMC5 gene and MLPA analysis for large deletion detection. In subjects with the ARMC5 variant, we searched ARMC5 gene somatic variants on tumor samples. Results: Among 10 PBMAH patients, we identified four ARMC5 germline variants (40%). One variant, c:174dupC p.Glu59Argfs*44, was already known; one variant p.Gly323Asp, was already reported and classified as likely disease-causing VUS (class 3–4); two variants p.Leu596Arg and p.Arg811Pro, were never reported before. For p.Gly323Asp and p.Arg811Pro, we identified second deleterious variants at the somatic level, enforcing the possible pathogenic effect of germline variants. Conclusions: Our results underscore the importance of performing genetic testing also in sporadic PBMAH patients and broaden the spectrum of molecular variants involved in PBMAH syndrome.