OLA1 gene sequencing in patients with BRCA1/2 mutation-negative suspected hereditary breast and ovarian cancer

Masanobu Takahashi, Natsuko Chiba, Hideki Shimodaira, Yuki Yoshino, Takahiro Mori, Makiko Sumii, Tadashi Nomizu, Chikashi Ishioka

Of individuals with suspected hereditary breast and ovarian cancer (HBOC), approximately 30-70 % do not harbor mutations in either BRCA1 or BRCA2 gene, which suggests that these individuals have other genetic or epigenetic alterations that could lead to the onset of this hereditary disease. We have recently identified OLA1 as a novel BRCA1/BARD1-interacting protein. In the present study, we aimed to elucidate whether any genetic mutations in OLA1 are detected among patients with suspected HBOC without BRCA1 or BRCA2 mutations. Among 53 patients with suspected HBOC enrolled at Hoshi General Hospital, 23 patients without any BRCA1 or BRCA2 mutations were analyzed for OLA1 mutations. Genomic DNA was extracted from the peripheral blood samples. PCR and Sanger sequencing were performed to elucidate whether there were any mutations in any of the ten exons and flanking introns of the OLA1 gene. No germline sequence variation was detected in the OLA1 gene among the 23 patients enrolled in this study. No germline mutations were found in the OLA1 gene among the cohort of patients with suspected HBOC without BRCA1 or BRCA2 mutations. Further studies are needed to clarify whether other mutations/epigenetic alterations are involved in the pathogenesis of BRCA1 or BRCA2 mutation-negative inherited disease with breast or ovarian cancer.