Albinism is characterized by a variable degree of hypopigmentation affecting the skin and the hair, and causing ophthalmologic abnormalities. Its oculocutaneous, ocular and syndromic forms follow an autosomal or X-linked recessive mode of inheritance, and 22 disease-causing genes are implicated in their development. Our aim was to clarify the genetic background of a Hungarian albinism cohort. Using a 22-gene albinism panel, the genetic background of 11 of the 17 Hungarian patients was elucidated. In patients with unidentified genetic backgrounds (n = 6), whole exome sequencing was performed. Our investigations revealed a novel, previously unreported rare variant (N687S) of the two-pore channel two gene (TPCN2). The N687S variant of the encoded TPC2 protein is carried by a 15-year-old Hungarian male albinism patient and his clinically unaffected mother. Our segregational analysis and in vitro functional experiments suggest that the detected novel rare TPCN2 variant alone is not a disease-causing variant in albinism. Deep genetic analyses of the family revealed that the patient also carries a phenotype-modifying R305W variant of the OCA2 protein, and he is the only family member harboring this genotype. Our results raise the possibility that this digenic combination might contribute to the observed differences between the patient and the mother, and found the genetic background of the disease in his case.

Accumulating evidence suggests that inherited melanoma is not rare and approx. one in seven individuals with melanoma has clinically relevant hereditable cancer-predisposing and/or -susceptibility variant(s). Concerning its germline genetic background, genetic screening aims to identify either variants of predisposing genes with high penetrance or variants of susceptibility genes with medium or low penetrance. However, less attention is paid to genetic testing of germline variants of genes influencing patients’ survival outcomes or enhancing the design of new therapies. We aimed to investigate whether the germline genetic background of a Hungarian melanoma cohort (n = 17) contains any pathogenic or likely pathogenic variants of the BRCA2, POLE, WRN, FANCI, PALB2, and RAD54B genes and if the presence of these variants correlate with the clinical findings of the patients, including the advanced stage of melanoma, poor prognosis, and poor survival. We identified three novel variants in the FANCI gene and one novel variant in the RAD54B gene. We detected rapid disease progression, unfavorable outcome, and therapeutic resistance in the patient carrying the likely pathogenic FANCI variant. Our study highlights the importance of screening germline variants of genes influencing melanoma progression, therapy resistance, and survival of patients.

Malignant melanoma is a complex malignancy with genetic, environmental, and lifestyle factors in its etiology. While germline variants in melanoma predisposition genes have been described, many patients remain genetically unexplained after panel testing. We previously analyzed a Hungarian melanoma cohort (n = 17), identifying variants in predisposing or susceptibility genes in 58.82% of patients. For individuals negative on this melanoma-specific panel, we expanded testing to a 19-gene panel associated with multiple cancer types. Next-generation sequencing was performed, followed by Sanger sequencing for confirmation. Variants were classified according to ACMG guidelines. In a 58-year-old female patient with a history of primary cutaneous melanoma, we identified a novel heterozygous frameshift variant in the tumor suppressor gene OBSCN (c.21322_21323insCTGG, p.G7108AfsTer10; NM_001386125.1). This insertion introduces a premature stop codon in exon 89 within the immunoglobulin-like domain, predicting protein truncation. Classified as likely pathogenic (PVS1, PM2), the variant is absent from population databases. To date, somatic OBSCN mutations have been reported in melanoma. This first report of a germline OBSCN frameshift variant in melanoma expands the genetic landscape of melanoma predisposition and suggests that OBSCN may represent a candidate gene contributing to melanoma risk.