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Background: Monoallelic germline pathogenic variants (GPVs) in five Fanconi anemia (FA) genes (BRCA1/FANCS, BRCA2/FANCD1, PALB2/FANCN, BRIP1/FANCJ, and RAD51C/FANCO) confer an increased risk of breast (BC) and/or ovarian (OC) cancer, but the role of GPVs in 17 other FA genes remains unclear., Methods: Here, we investigated the association of germline variants in FANCG/XRCC9 with BC and OC risk., Results: The frequency of truncating GPVs in FANCG did not differ between BC (20/10,204; 0.20%) and OC (8/2966; 0.27%) patients compared to controls (6/3250; 0.18%). In addition, only one out of five tumor samples showed loss-of-heterozygosity of the wild-type FANCG allele. Finally, none of the nine functionally tested rare recurrent missense FANCG variants impaired DNA repair activities (FANCD2 monoubiquitination and FANCD2 foci formation) upon DNA damage, in contrast to all tested FANCG truncations., Conclusion: Our study suggests that heterozygous germline FANCG variants are unlikely to contribute to the development of BC or OC., (© 2024 The Author(s). Cancer Medicine published by John Wiley & Sons Ltd.)

Germline CHEK2 pathogenic variants confer an increased risk of female breast cancer (FBC). Here we describe a recurrent germline intronic variant c.1009-118_1009-87delinsC, which showed a splice acceptor shift in RNA analysis, introducing a premature stop codon (p.Tyr337PhefsTer37). The variant was found in 21/10,204 (0.21%) Czech FBC patients compared to 1/3250 (0.03%) controls (p = 0.04) and in 4/3639 (0.11%) FBC patients from an independent German dataset. In addition, we found this variant in 5/2966 (0.17%) Czech (but none of the 443 German) ovarian cancer patients, three of whom developed early-onset tumors. Based on these observations, we classified this variant as likely pathogenic., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Ovarian cancer (OC) is the deadliest gynecologic malignancy with a substantial proportion of hereditary cases and a frequent association with breast cancer (BC). Genetic testing facilitates treatment and preventive strategies reducing OC mortality in mutation carriers. However, the prevalence of germline mutations varies among populations and many rarely mutated OC predisposition genes remain to be identified. We aimed to analyze 219 genes in 1333 Czech OC patients and 2278 population-matched controls using next-generation sequencing. We revealed germline mutations in 18 OC/BC predisposition genes in 32.0% of patients and in 2.5% of controls. Mutations in BRCA1/BRCA2 , RAD51C/RAD51D , BARD1 , and mismatch repair genes conferred high OC risk (OR > 5). Mutations in BRIP1 and NBN were associated with moderate risk (both OR = 3.5). BRCA1/2 mutations dominated in almost all clinicopathological subgroups including sporadic borderline tumors of ovary (BTO). Analysis of remaining 201 genes revealed somatic mosaics in PPM1D and germline mutations in SHPRH and NAT1 associating with a high/moderate OC risk significantly; however, further studies are warranted to delineate their contribution to OC development in other populations. Our findings demonstrate the high proportion of patients with hereditary OC in Slavic population justifying genetic testing in all patients with OC, including BTO.

Background and Aim: Osteogenesis imperfecta (OI), also called brittle bone disease, is a clinically and genetically heterogeneous disorder characterized by decreased bone density. Autosomal dominant forms result from mutations in either the COL1A1 (collagen type I alpha-1 chain) or COL1A2 (collagen type I alpha-2 chain) genes encoding the type I collagen. The aim of this study was to identify mutations and allelic variants of the COL1A1 gene in patients with osteogenesis imperfecta (OI)., Methods and Results: Molecular genetic analysis of the COL1A1 gene was performed in a cohort of 34 patients with OI. The DNA samples were analysed by PCR and Sanger sequencing. DNA changes in coding sequences of the gene were compared with Type 1 Collagen Mutation Database. Genetic variants resulting in either quantitatively or structurally defective protein production were found in 6 unrelated patients. Four identified mutations are connected to decreased protein production (Tyr47X, Arg131X, Arg415X, Gln1341X), 2 result in amino acid substitution (Cys61Phe, Pro1186Ala) and the last affects splicing (c.1057-1G>T). Further, one silent mutation (Gly794Gly) was detected. No protein analysis was performed., Conclusion: Of the 8 identified mutations, 5 were novel and have not been reported before. Only one causes substitution of glycine located within the Gly-X-Y triplets in the triple helical domain. Two mutations are located in major ligand binding regions (MLBR) which are important for bone strength and flexibility. Although the genotype-phenotype correlation is still unclear, our findings should contribute to elucidating this relationship in patients diagnosed with OI.