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Fanconi anemia (FA) is an inherited bone marrow failure syndrome (IBMFS) characterized by pathogenic variants in the FA/BRCA DNA repair pathway genes. Individuals with FA have an elevated risk of developing myelodysplastic syndrome, acute myeloid leukemia, and solid tumors. Hematopoietic cell transplantation (HCT) is the most effective treatment for FA related bone marrow failure but can increase the risk of cancer development. Information on benign tumors and NMSC is lacking in patients with FA. Our objective was to characterize patients with FA enrolled in the National Cancer Institute IBMFS Study who have experienced non-melanoma skin cancers (NMSC) and/or benign tumors (BT). A total of 200 patients diagnosed with FA were enrolled in the Institutional Review Board approved study "Etiologic Investigation of Cancer Susceptibility in IBMFS: A Natural History Study" (NCT00027274). Through medical records review, we identified 30 patients with at least one NMSC, either squamous or basal cell carcinoma, or benign tumor. The remaining 170 patients comprised the control group. Out of 200 patients, 12 had NMSC, 25 had benign tumors, with an age range of 11–64 and 0–56 years, respectively. The median age at HCT was 30.5 years for NMSC patients, 9 years for benign tumor patients, and 9.1 years for controls. The most common genotype observed was FANCA, followed by FANCC and FANCI. Benign tumors spanned diverse anatomical locations. Early onset NMSC in patients with FA compared to the general population emphasizes the need for consistent monitoring in patients with FA, while the diverse anatomical locations of benign tumors underscore the importance of comprehensive surveillance for timely interventions in managing symptomatology and heightened cancer risk. [ABSTRACT FROM AUTHOR]

Fanconi anemia (FA) is generally classified as a DNA repair disorder, conferring a genetic predisposition to cancer and prominent bone marrow failure (BMF) in early childhood. Corroborative human and murine studies point to a fetal origin of hematopoietic stem cell (HSC) attrition under replicative stress. Along with intriguing recent insights into non‐canonical roles and domain‐specific functions of FA proteins, these studies have raised the possibility of a DNA repair‐independent BMF etiology. However, deeper mechanistic insight is critical as current curative options of allogeneic stem cell transplantation and emerging gene therapy have limited eligibility, carry significant side effects, and involve complex procedures restricted to resource‐rich environments. To develop rational and broadly accessible therapies for FA patients, the field will need more faithful disease models that overcome the scarcity of patient samples, leverage technological advances, and adopt investigational clinical trial designs tailored for rare diseases. [ABSTRACT FROM AUTHOR]

Chromothripsis describes the catastrophic shattering of mis-segregated chromosomes trapped within micronuclei. Although micronuclei accumulate DNA double-strand breaks and replication defects throughout interphase, how chromosomes undergo shattering remains unresolved. Using CRISPR-Cas9 screens, we identify a non-canonical role of the Fanconi anemia (FA) pathway as a driver of chromothripsis. Inactivation of the FA pathway suppresses chromosome shattering during mitosis without impacting interphase-associated defects within micronuclei. Mono-ubiquitination of FANCI-FANCD2 by the FA core complex promotes its mitotic engagement with under-replicated micronuclear chromosomes. The structure-selective SLX4-XPF-ERCC1 endonuclease subsequently induces large-scale nucleolytic cleavage of persistent DNA replication intermediates, which stimulates POLD3-dependent mitotic DNA synthesis to prime shattered fragments for reassembly in the ensuing cell cycle. Notably, FA-pathway-induced chromothripsis generates complex genomic rearrangements and extrachromosomal DNA that confer acquired resistance to anti-cancer therapies. Our findings demonstrate how pathological activation of a central DNA repair mechanism paradoxically triggers cancer genome evolution through chromothripsis. [Display omitted] • The FA pathway promotes the catastrophic shattering of micronuclear chromosomes • SLX4-XPF-ERCC1 cleaves mitotic DNA replication intermediates from micronuclei • MiDAS facilitates the mutagenic reassembly of shattered chromosomes in interphase • FA-induced mitotic shattering drives genome rearrangements and ecDNA formation A genetic screen uncovers the Fanconi anemia pathway as a driver of chromothripsis by shattering under-replicated micronuclear chromosomes during mitosis. This process involves chromosome-scale cleavage by the SLX4-XPF-ERCC1 endonuclease coupled to mitotic DNA synthesis, resulting in complex rearrangements and ecDNAs that fuel cancer genome evolution and/or resistance to anti-cancer therapies. [ABSTRACT FROM AUTHOR]

Fanconi anemia (FA) is a rare genetic disease characterized by congenital abnormalities and increased risk for bone marrow failure and cancer. Central nervous system defects, including acute and irreversible loss of neurological function and white matter lesions with calcifications, have become increasingly recognized among FA patients, and are collectively referred to as Fanconi Anemia Neurological Syndrome or FANS. The molecular etiology of FANS is poorly understood. In this study, we have used a functional integrative genomics approach to further define the function of the FANCD2 protein and FA pathway. Combined analysis of new and existing FANCD2 ChIP-seq datasets demonstrates that FANCD2 binds nonrandomly throughout the genome with binding enriched at transcription start sites and in broad regions spanning protein-coding gene bodies. FANCD2 demonstrates a strong preference for large neural genes involved in neuronal differentiation, synapse function, and cell adhesion, with many of these genes implicated in neurodevelopmental and neuropsychiatric disorders. Furthermore, FANCD2 binds to regions of the genome that replicate late, undergo mitotic DNA synthesis (MiDAS) under conditions of replication stress, and are hotspots for copy number variation. Our analysis describes an important targeted role for FANCD2 and the FA pathway in the maintenance of large neural gene stability. [ABSTRACT FROM AUTHOR]

Introduction: Fanconi anemia (FA) is a genomic instability disorder associated with congenital abnormalities, including short stature and the presence of central nervous system anomalies, especially in the hypothalamic-pituitary area. Thus, differences in pituitary size could associate with the short stature observed in these patients. Our aim was to evaluate whether central nervous system abnormalities and pituitary gland volume correlate with height and hormone deficiencies in these patients. Methods: In this cross-sectional exploratory study 21 patients diagnosed with FA between 2017 and 2022 in a Spanish Reference Center were investigated. Magnetic resonance imaging (MRI) was performed and pituitary volume calculated and corelated with height and other endocrine parameters. Results: The percentage of abnormalities in our series was 81%, with a small pituitary (pituitary volume less than 1 SD) being the most frequent, followed by Chiari malformation type 1. The median value of pituitary volume was -1.03 SD (IQR: -1.56, -0.36). Short stature was found in 66.7% [CI95% 43-85.4]. Total volume (mm3) increases significantly with age and in pubertal stages. Therewere no differences between volume SD and pubertal stage, or the presence of endocrine deficiencies. No correlations were found between pituitary volume and the presence of short stature. The intraclass correlation index (ICC) average for volume was 0.85 [CI95% 0.61-0.94] indicating a good-to-excellent correlation of measurements. Discussion: Central nervous systemanomalies are part of the FA phenotype, the most frequent after pituitary hypoplasia being posterior fossa abnormalities, whichmay have clinical repercussions in the patient. It is therefore necessary to identify those who could be candidates for neurosurgical intervention. The size of the pituitary gland is smaller in these patients, but this does not seem to be related to hormone deficiency and short stature or exposure to a low dose of total body irradiation. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the oral health-related quality of life (OHRQoL) of individuals diagnosed with Fanconi anemia (FA). Methods: A cross-sectional study was conducted with FA patients from two Brazilian referral centers. Participants underwent a complete dental, periodontal, and oral mucosa examination, as well as assessment of resting salivary flow. The short version of the Oral Health Impact Profile (OHIP-14) questionnaire was administered. Descriptive and bivariate analyses were performed, followed by multivariate analysis to examine the impact of independent variables on OHRQoL. Results: The study included 20 (57.1%) males and 15 (42.9%) females, with a mean age of 18.9 years. Oral leukoplakia (OL) was found in 18 individuals. The overall OHIP-14 score was 9.9 ± 10.5. Individuals aged ≥ 16 years had higher OHIP-14 scores, indicating worse OHRQoL for physical pain (p = 0.007), psychological discomfort (p = 0.001), physical disability (p = 0.03), psychological disability (p = 0.001), handicap (p = 0.004), and overall score (p = 0.007). Females reported more negative OHRQoL than males for physical pain (p = 0.02), psychological discomfort (p = 0.03), psychological disability (p = 0.009), and overall score (p = 0.02). Individuals with OL had an overall OHIP-14 score 1.83 times higher than those without OL (95% CI: 1.02–3.28; p = 0.04). Lower salivary flow correlated with higher overall OHIP-14 scores (95% CI: 0.14–0.84; p = 0.01). Conclusion: This study represents the first attempt to evaluate OHRQoL in individuals with FA. The presence of OL and reduced salivary flow were identified as predictors of a negative impact on OHRQoL. It is imperative to integrate patients' quality of life in the clinical treatment protocols for the FA population. [ABSTRACT FROM AUTHOR]

Fanconi anemia (FA), dyskeratosis congenita-related telomere biology disorders (DC/TBD), and Diamond–Blackfan anemia (DBA) are inherited bone marrow failure syndromes (IBMFS) with high risks of bone marrow failure, leukemia, and solid tumors. Individuals with FA have reduced fertility. Previously, we showed low levels of anti-Müllerian hormone (AMH), a circulating marker of ovarian reserve, in females with IBMFS. In males, AMH may be a direct marker of Sertoli cell function and an indirect marker of spermatogenesis. In this study, we assessed serum AMH levels in pubertal and postpubertal males with FA, DC/TBD, or DBA and compared this with their unaffected male relatives and unrelated healthy male volunteers. Males with FA had significantly lower levels of AMH (median: 5 ng/mL, range: 1.18–6.75) compared with unaffected male relatives (median: 7.31 ng/mL, range: 3.46–18.82, P = 0.03) or healthy male volunteers (median: 7.66 ng/mL, range: 3.3–14.67, P = 0.008). Males with DC/TBD had lower levels of AMH (median: 3.76 ng/mL, range: 0–8.9) compared with unaffected relatives (median: 5.31 ng/mL, range: 1.2–17.77, P = 0.01) or healthy volunteers (median: 5.995 ng/mL, range: 1.57–14.67, P < 0.001). Males with DBA had similar levels of AMH (median: 3.46 ng/mL, range: 2.32–11.85) as unaffected relatives (median: 4.66 ng/mL, range: 0.09–13.51, P = 0.56) and healthy volunteers (median: 5.81 ng/mL, range: 1.57–14.67, P = 0.10). Our findings suggest a defect in the production of AMH in postpubertal males with FA and DC/TBD, similar to that observed in females. These findings warrant confirmation in larger prospective studies.

Introduction: Fanconi anemia (FA) is an inherited disorder characterized by bone marrow failure, congenital malformations, and predisposition to malignancies. Alterations in hematopoietic stem cells (HSC) have been reported, but little is known regarding the bone marrow (BM) stroma. Thus, the characterization of Mesenchymal Stromal Cells (MSC) would help to elucidate their involvement in the BM failure. Methods: We characterized MSCs of 28 FA patients (FA-MSC) before and after treatment (hematopoietic stem cell transplantation, HSCT; or gene therapy, GT). Phenotypic and functional properties were analyzed and compared with MSCs expanded from 26 healthy donors (HD-MSCs). FA-MSCs were genetically characterized through, mitomycin C-test and chimerism analysis. Furthermore, RNA-seq profiling was used to identify dysregulated metabolic pathways. Results: Overall, FA-MSC had the same phenotypic and functional characteristics as HD-MSC. Of note, MSC-GT had a lower clonogenic efficiency. These findings were not confirmed in the whole FA patients' cohort. Transcriptomic profiling identified dysregulation in HSC self-maintenance pathways in FA-MSC (HOX), and was confirmed by real-time quantitative polymerase chain reaction (RT-qPCR). Discussion: Our study provides a comprehensive characterization of FA-MSCs, including for the first time MSC-GT and constitutes the largest series published to date. Interestingly, transcript profiling revealed dysregulation of metabolic pathways related to HSC self-maintenance. Taken together, our results or findings provide new insights into the pathophysiology of the disease, although whether these niche defects are involved in the hematopoietic defects seen of FA deserves further investigation. [ABSTRACT FROM AUTHOR]

Acute promyelocytic leukemia (APL) represents 5%–10% of childhood acute myeloid leukemia (AML) and is the most curable subtype of AML. Fanconi anemia (FA) is one of the most common inherited bone marrow failure syndromes caused by biallelic pathogenic variants (PV) in specific DNA‐repair genes. Biallelic PVs in FANCD1/BRCA2 (FA‐D1) account for 3% of FA and are associated with early‐onset leukemia and a high risk of solid tumors. We report a 4 year‐old boy from non‐consanguineous parents diagnosed with standard risk APL. This child had café‐au‐lait spots and an extra thumb remnant. Genomic sequencing revealed two PV in FANCD1/BRCA2 confirming a diagnosis of FA‐D1. Chromosomal breakage studies were compatible with FA. Each parent carried one variant and had no personal history of cancer. Morphological then molecular remissions were achieved with all‐trans retinoic acid and Arsenic trioxide. This patient underwent haploidentical stem cell transplant. In addition to our patient, a literature search revealed four additional patients with APL/FA, with a total of three patients with FA‐D1. This raises the possibility of an association between such rare disorders. Practical management of APL in the setting of FA‐D1 is discussed with an overview of current evidence and knowledge gaps. [ABSTRACT FROM AUTHOR]

Fanconi anemia, a rare disorder with an incidence of 1 in 300,000, is caused by mutations in FANC genes, which affect the repair of DNA interstrand crosslinks. The disease is characterized by congenital malformations, bone marrow failure within the first decade of life, and recurrent squamous cell carcinomas of the oral cavity, esophagus, and anogenital regions starting around age 20. In this review, we propose that Fanconi anemia should be considered a premature-aging syndrome. Interestingly, the onset and severity of the life-limiting clinical features of Fanconi anemia can be influenced by lifestyle choices, such as a healthy diet and physical activity. These factors shape the epigenetic status of at-risk cell types and enhance the competence of the immune system through nutritional signaling. Fanconi anemia may serve as a model for understanding the aging process in the general population, addressing research gaps in its clinical presentation and suggesting prevention strategies. Additionally, we will discuss how the balance of genetic and environmental risk factors—affecting both cancer onset and the speed of aging—is interlinked with signal transduction by dietary molecules. The underlying nutrigenomic principles will offer guidance for healthy aging in individuals with Fanconi anemia as well as for the general population. [ABSTRACT FROM AUTHOR]

Fanconi anemia is the most common hereditary bone marrow failure syndrome; in these patients usually develops progressively, and hematological complications may worsen during adolescence and early adulthood, leading to the development of neoplasmassociated conditions such as myelodysplastic syndromes and acute myeloid leukemia. The onset and evolution toward neoplasia in Fanconi anemia, has been associated with losses and gains of chromosomal regions, and can be monitored by searching for clonal cytogenetic alterations located on chromosomes 1, 3 and 7 being characteristic of the disease. In this article, we present the methodology used by our laboratory to detect and monitor chromosome alterations, using banding GTG and fluorescence in situ hybridization techniques. This strategy represents a cost-effective way to perform longitudinal monitoring of changes in the bone marrow of patients, which, together with morphological analysis and monitoring of peripheral blood counts, allows timely therapeutic decisions to be made, such as programming transplantation of hematopoietic stem and progenitor cells, when possible. [ABSTRACT FROM AUTHOR]

Some years ago, we reported the generation of a Fanconi anemia (FA) microRNA signature. This study aims to develop an analytical strategy to select a smaller and more reliable set of molecules that could be tested for potential benefits for the FA phenotype, elucidate its biochemical and molecular mechanisms, address experimental activity, and evaluate its possible impact on FA therapy. In silico analyses of the data obtained in the original study were thoroughly processed and anenrichment analysis was employed to identify the classes of genes that are over-represented in the FA-miRNA population under study. Primary bone marrow mononuclear cells (MNCs) from sixFA patients and sixhealthy donors as control samples were employed in the study. RNAs containing the small RNA fractions were reverse-transcribed and real-time PCR was performed in triplicate using the specific primers. Experiments were performed in triplicate.The in-silico analysis reported six miRNAs as likely contributors to the complex pathological spectrum of FA. Among these, three miRNAs were validated by real-time PCR. Primary bone marrow mononuclear cells (MNCs) reported a significant reduction in the expression level of miRNA-1246 and miRNA-206 in the FA samples in comparison to controls.This study highlights several biochemical pathways as culprits in the phenotypic manifestations and the pathophysiological mechanisms acting in FA. A relatively low number of miRNAs appear involved in all these different phenotypes, demonstrating the extreme plasticity of the gene expression modulation. This study further highlights miR-206 as a pivotal player in regulatory functions and signaling in the bone marrow mesenchymal stem cell (BMSC) process in FA. Due to this evidence, the activity of miR-206 in FA deserves specific experimental scrutiny. The results, here presented, might be relevant in the management of FA. [ABSTRACT FROM AUTHOR]

Patients with Fanconi anemia (FA) are often perceived to have poor growth when general population growth curves are utilized. We hypothesize that FA patients have unique growth and aimed to create FA‐specific growth charts. Height and weight data from ages 0 to 20 years were extracted from medical records of patients treated at the Fanconi Anemia Comprehensive Care Clinic at the University of Minnesota. Height, weight, and BMI growth curves were generated and fitted to reference percentiles using the Lambda‐Mu‐Sigma method. FA‐specific percentiles were compared to WHO standards for ages 0–2 and CDC references for ages 2–20. In FA males, the 50th height‐ and weight‐for‐age percentiles overlap with the 3rd reference percentile. In FA females, only the 50th height‐for‐age percentile overlaps with the 3rd reference percentile. For weight, FA females show progressive growth failure between 6 and 24 months followed by stabilization around the 50th percentile. The FA BMI‐for‐age percentiles show similar patterns to the weight‐for‐age percentiles but have different timing of onset of adiposity rebound and broader variability in females. Growth in FA patients follows a different trajectory than available normative curves. FA‐specific growth charts may be useful to better guide accurate growth expectations, evaluations, and treatment. [ABSTRACT FROM AUTHOR]

The Smc5/6 complex is a highly conserved molecular machine involved in the maintenance of genome integrity. While its functions largely depend on restraining the fork remodeling activity of Mph1 in yeast, the presence of an analogous Smc5/6-FANCM regulation in humans remains unknown. We generated human cell lines harboring mutations in the NSE1 subunit of the Smc5/6 complex. Point mutations or truncations in the RING domain of NSE1 result in drastically reduced Smc5/6 protein levels, with differential contribution of the two zinc-coordinating centers in the RING. In addition, nse1-RING mutant cells display cell growth defects, reduced replication fork rates, and increased genomic instability. Notably, our findings uncover a synthetic sick interaction between Smc5/6 and FANCM and show that Smc5/6 controls fork progression and chromosome disjunction in a FANCM-independent manner. Overall, our study demonstrates that the NSE1 RING domain plays vital roles in Smc5/6 complex stability and fork progression through pathways that are not evolutionary conserved. [ABSTRACT FROM AUTHOR]

Introduction: Fanconi anemia (FA) is a rare autosomal recessive disease characterized by chromosomal instability and increased predisposition to malignancy. The diagnosis of FA requires clinical evaluation, confirmation of chromosomal fragility and/or analysis of genetic mutations. Therefore, this study aims to identify the clinical profile of patients with FA in the state of Pernambuco, Brazil. Method: We analyzed 100 individuals referred from the major hematology and bone marrow (BM) transplant centers in the state of Pernambuco, Brazil, between the years 2018 and 2022. The diagnosis of FA was performed using the mitomycin C chromosomal fragility test, clinical data and classical and molecular cytogenetic analyses. Results: We enrolled a total of 16 patients with FA to comprise this study. Most of these individuals (87.5%) came from the Agreste and Sertão regions of Pernambuco. We observed a slight female prevalence of FA (1.3:1). The primary clinical and laboratory findings were café au lait spots (62.5%) and bone abnormalities (53%, mainly thumb deformities [40%]). We performed BM cytogenetic analysis for eight patients – seven showed no chromosomal abnormalities and one presented the karyotype 47,XY,+21 [15]. Conclusions: Our results are important to promote public health measures for the early diagnosis of FA, as well as to foster the engagement of a multidisciplinary group in the treatment of this disease.

Abstract Fanconi Anemia (FA) pathway resolves DNA interstrand cross links (ICL). The FA pathway was initially recognized in vertebrates, but was later confirmed in other animals and speculated in fungi. FA proteins FANCM, FANCL and FANCJ are present in Saccharomyces cerevisiae but, their mechanism of interaction to resolve ICL is still unclear. Unlike Dikarya, early diverging fungi (EDF) possess more traits shared with animals. We traced the evolutionary history of the FA pathway across Opisthokonta. We scanned complete proteomes for FA-related homologs to establish their taxonomic distribution and analyzed their phylogenetic trees. We checked transcription profiles of FA genes to test if they respond to environmental conditions and their genomic localizations for potential co-localization. We identified fungal homologs of the activation and ID complexes, 5 out of 8 core proteins, all of the endonucleases, and deubiquitination proteins. All fungi lack FANCC, FANCF and FANCG proteins responsible for post-replication repair and chromosome stability in animals. The observed taxonomic distribution can be attributed to a gradual degradation of the FA pathway from EDF to Dikarya. One of the key differences is that EDF have the ID complex recruiting endonucleases to the site of ICL. Moreover, 21 out of 32 identified FA genes are upregulated in response to different growth conditions. Several FA genes are co-localized in fungal genomes which also could facilitate co-expression. Our results indicate that a minimal FA pathway might still be functional in Mucoromycota with a gradual loss of components in Dikarya ancestors.

Abstract Constitutional heterozygous pathogenic variants in genes coding for some components of the Fanconi anemia-BRCA signaling pathway, which repairs DNA interstrand crosslinks, represent risk factors for common cancers, including breast, ovarian, pancreatic and prostate cancer. A high cancer risk is also a main clinical feature in patients with Fanconi anemia (FA), a rare condition characterized by bone marrow failure, endocrine and physical abnormalities. The mainly recessive condition is caused by germline pathogenic variants in one of 21 FA-BRCA pathway genes. Among patients with FA, the highest cancer risks are observed in patients with biallelic pathogenic variants in BRCA2 or PALB2. These patients develop a range of embryonal tumors and leukemia during the first decade of life, however, little is known about specific clinical, genetic and pathologic features or toxicities. Here, we present genetic, clinical, pathological and treatment characteristics observed in an international cohort of eight patients with FA due to biallelic BRCA2 pathogenic variants and medulloblastoma (MB), an embryonal tumor of the cerebellum. Median age at MB diagnosis was 32.5 months (range 7–58 months). All patients with available data had sonic hedgehog-MB. Six patients received chemotherapy and one patient also received proton radiation treatment. No life-threatening toxicities were documented. Prognosis was poor and all patients died shortly after MB diagnosis (median survival time 4.5 months, range 0–21 months) due to MB or other neoplasms. In conclusion, MB in patients with biallelic BRCA2 pathogenic variants is a lethal disease. Future experimental treatments are necessary to help these patients.

Esophageal atresia/tracheoesophageal fistula (EA/TEF) is a life-threatening birth defect that often occurs with other major birth defects (EA/TEF+). Despite advances in genetic testing, a molecular diagnosis can only be made in a minority of EA/TEF+ cases. Here, we analyzed clinical exome sequencing data and data from the DECIPHER database to determine the efficacy of exome sequencing in cases of EA/TEF+ and to identify phenotypic expansions involving EA/TEF. Among 67 individuals with EA/TEF+ referred for clinical exome sequencing, a definitive or probable diagnosis was made in 11 cases for an efficacy rate of 16% (11/67). This efficacy rate is significantly lower than that reported for other major birth defects, suggesting that polygenic, multifactorial, epigenetic, and/or environmental factors may play a particularly important role in EA/TEF pathogenesis. Our cohort included individuals with pathogenic or likely pathogenic variants that affect TCF4 and its downstream target NRXN1, and FANCA, FANCB, and FANCC, which are associated with Fanconi anemia. These cases, previously published case reports, and comparisons to other EA/TEF genes made using a machine learning algorithm, provide evidence in support of a potential pathogenic role for these genes in the development of EA/TEF.