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Shwachman-Diamond syndrome represents a clinically and genetically heterogeneous disorder. We report on an infant with a very severe, fatal clinical course caused by biallelic EFL1 variants: c.89A>G, p.(His30Arg), and c.2599A>G, p.(Asn867Asp). Functional analysis of patient-derived B-lymphoblastoid and SV40-transformed fibroblast cell lines suggests that the compound heterozygous EFL1 variants impaired mature ribosome formation leading to compromised protein synthesis, ultimately resulting in a severe form of Shwachman-Diamond syndrome., (© 2024 The Author(s). British Journal of Haematology published by British Society for Haematology and John Wiley & Sons Ltd.)

Shwachman-Diamond syndrome (SDS) is an inherited bone marrow failure disorder that often presents at infancy. Progress has been made in revealing causal mutated genes (SBDS and others), ribosome defects, and hematopoietic aberrations in SDS. However, the mechanism underlying the hematopoietic failure remained unknown, and treatment options are limited. Herein, we investigated the onset of SDS embryonic hematopoietic impairments. We generated SDS and control human-derived induced pluripotent stem cells (iPSCs). SDS iPSCs recapitulated the SDS hematological phenotype. Detailed stepwise evaluation of definitive hematopoiesis revealed defects that started at the early emerging hematopoietic progenitor (EHP) stage after mesoderm and hemogenic endothelium were normally induced. Hematopoietic potential of EHPs was markedly reduced, and the introduction of SBDS in SDS iPSCs improved colony formation. Transcriptome analysis revealed reduced expression of ribosome and oxidative phosphorylation-related genes in undifferentiated and differentiated iPSCs. However, certain pathways (e.g., DNA replication) and genes (e.g., CHCHD2) were exclusively or more severely dysregulated in EHPs compared with earlier and later stages. To our knowledge, this study offers for the first time an insight into the embryonic onset of human hematopoietic defects in an inherited bone marrow failure syndrome and reveals cellular and molecular aberrations at critical stages of hematopoietic development toward EHPs., (© 2024 The Author(s). European Journal of Haematology published by John Wiley & Sons Ltd.)

Rationale: Shwachman-Diamond syndrome (SDS) is a rare autosomal recessive genetic disease, the diagnosis is a big challenge for clinician, as the clinical manifestations of the disease are diverse. Here, we report a girl who diagnosed with SDS with the symptoms of recurrent fever, elevated transaminase levels, and granulocytosis. The aspects of diagnosis and treatment were discussed and a literature review was conducted., Patient Concerns: A 15-month-old girl admitted to our hospital because of recurrent fever, granulocytopenia, and elevated transaminase levels., Diagnosis and Interventions: The compound heterozygous variant of Shwachman-Bodian-Diamond syndrome c.258 + 2T > C:p.84Cfs3 and c.96C > G:p.Y32* were detected after sequencing the blood samples from the patient and her parents. Finally, she was diagnosed with SDS and she was treated with compound glycyrrhizin, granulocyte-colony stimulating factor, and antibiotic in the case of co-infection., Outcomes: During the follow-up, her liver function showed the level of transaminases decreased and she rarely had infection after the age of 15 months although neutropenia is still present., Lessons: Patients with SDS lacks typical clinical symptoms, which presents a huge challenge for clinicians. Genetic testing techniques is playing an important role in the diagnosis of diseases. This patient without typical clinical manifestations such as exocrine pancreatic insufficiency and skeletal abnormality, we report this case aimed to strengthen the understanding of the disease., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.)

Background: Congenital neutropenias are characterized by severe infections and a high risk of myeloid transformation; the causative genes vary across ethnicities. The Israeli population is characterized by an ethnically diverse population with a high rate of consanguinity., Objective: To evaluate the clinical and genetic spectrum of congenital neutropenias in Israel., Methods: We included individuals with congenital neutropenias listed in the Israeli Inherited Bone Marrow Failure Registry. Sanger sequencing was performed for ELANE or G6PC3, and patients with wild-type ELANE/G6PC3 were referred for next-generation sequencing., Results: Sixty-five patients with neutropenia were included. Of 51 patients with severe congenital neutropenia, 34 were genetically diagnosed, most commonly with variants in ELANE (15 patients). Nine patients had biallelic variants in G6PC3, all of consanguineous Muslim Arab origin. Other genes involved were SRP54, JAGN1, TAZ, and SLC37A4. Seven patients had cyclic neutropenia, all with pathogenic variants in ELANE, and seven had Shwachman-Diamond syndrome caused by biallelic SBDS variants. Eight patients (12%) developed myeloid transformation, including six patients with an unknown underlying genetic cause. Nineteen (29%) patients underwent hematopoietic stem cell transplantation, mostly due to insufficient response to treatment with granulocyte-colony stimulating factor or due to myeloid transformation., Conclusions: The genetic spectrum of congenital neutropenias in Israel is characterized by a high prevalence of G6PC3 variants and an absence of HAX1 mutations. Similar to other registries, for 26% of the patients, a molecular diagnosis was not achieved. However, myeloid transformation was common in this group, emphasizing the need for close follow-up., (© 2024 The Authors. European Journal of Haematology published by John Wiley & Sons Ltd.)

This study reports on three patients with Shwachman-Diamond syndrome (SDS) who underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) at the First Affiliated Hospital of Zhejiang University School of Medicine. Based on relevant literature, the clinical manifestations and genetic mutation characteristics of SDS were summarized, and the efficacy and timing of allo HSCT for such patients were explored. Three SDS patients were all male, with transplant ages of 32, 33, and 32 years old, respectively. All three patients were diagnosed in childhood. Case 1 presented with anemia as the initial clinical manifestation, which gradually progressed to a decrease in whole blood cells; Case 2 and 3 both present with a decrease in whole blood cells as the initial clinical manifestation. Case 1 and 3 have intellectual disabilities, while case 3 presents with pancreatic steatosis and chronic pancreatitis. All three patients have short stature. Three patients all detected heterozygous mutations in the SBDS: c.258+2T>C splice site. The family members of the three patients have no clinical manifestations of SDS. All three patients were treated with a reduced dose pre-treatment regimen (Fludarabine+Busulfan+Me-CCNU+Rabbit Anti-human Thymocyte Globulin). Case 1 and case 2 underwent haploid hematopoietic stem cell transplantation, while case 3 underwent unrelated donor hematopoietic stem cell transplantation. Case 1 was diagnosed with myelodysplastic syndrome transforming into acute myeloid leukemia before transplantation, but experienced early recurrence and death after transplantation; Case 2 is secondary implantation failure, dependent on platelet transfusion; Case 3 was removed from medication maintenance treatment after transplantation, and blood routine monitoring was normal.

Shwachman Diamond syndrome (SDS) is a rare autosomal recessive genetic disorder and due to its complex and varied clinical manifestations, diagnosis is often delayed. The purpose of this study was to investigate the clinical manifestations and genetic characteristics of SDS in Chinese patients, in order to increase pediatricians' awareness of SDS and to allow early diagnosis. We conducted a search to identify patients presenting SBDS gene pathogenic variant in two Chinese academic databases. We analyzed and summarized the epidemiology, clinical features, gene pathogenic variants, and key points in the diagnosis and treatment of SDS. We reviewed the clinical data of 39 children with SDS from previously published articles. The interval from the onset of the first symptoms to diagnosis was very long for most of our patients. The age of presentation ranged from 1 day to 10 years (median: 3 months). However, the age of diagnosis was significantly delayed, ranging from 1 month to 14 years (median: 14 months). Hematological abnormalities were the most common presentation, 89.7% (35/39) at the beginning and 94.9% (37/39) at diagnosis of SDS. Diarrhea was the second most common clinical abnormality at the time of diagnosis. 59% (23/39) of patients had a typical history of persistent chronic diarrhea. Furthermore, hepatic enlargement or elevation of transaminase occurred in 15 cases (38.5%). 56.4% patients (22/39) had a short stature, and 17.9% (7/39) patients showed developmental delay. Additionally, twenty patients had compound heterozygous pathogenic variants of c.258 + 2T > C and c.183_ 184TA > CT. Children with SDS in China had high incidence rates of chronic diarrhea, cytopenia, short stature, and liver damage. Furthermore, SBDS c.258 + 2T > C and c.183_ 184TA > CT were the most common pathogenic variants in patients with SDS. The diagnosis of SDS can be delayed if the clinical phenotype is not recognized by the health care provider., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Wang, Jin, Chen, Zhao, Shang, Liu and Sun.)

Shwachman-Diamond syndrome (SDS) is one of the most common inherited bone marrow failure syndromes. SDS is characterized by hypocellular bone marrow, with a severe impairment of the myeloid lineage, resulting in neutropenia, thrombocytopenia, and, more rarely, anemia. Almost 15% of patients with SDS develop myelodysplastic syndrome or acute myeloid leukemia as early as childhood or young adulthood. Exocrine pancreatic insufficiency is another common feature of SDS. Almost all patients with SDS show failure to thrive, which is associated with skeletal abnormalities due to defective ossification. Considering these observations, it remains unfeasible to use the common growth charts already available for the general population. To address this issue, we report how we drew up growth charts of patients with SDS aged 0 to 18 years. We analyzed height, weight, and body max index (BMI) in 121 Italian patients with SDS. Results indicated that the 50th and 3rd percentiles of weight and height of the pediatric general population correspond to the 97th and 50th percentiles of patients with SDS aged 0-18 years, respectively. In addition, the percentage increment in weight of subjects aged 14-18 years was higher in patients with SDS than in the general population. SDS-specific growth charts, such as those described here, afford a new tool, which is potentially useful for both clinical and research purposes in SDS.

Shwachman-Diamond syndrome (SDS) is an autosomal recessive disorder characterized by exocrine pancreatic insufficiency and bone marrow failure. The depletion of SBDS protein by RNA interference has been shown to cause inhibition of cell proliferation in several cell lines. However, the precise mechanism by which the loss of SBDS leads to inhibition of cell growth remains unknown. To evaluate the impaired growth of SBDS-knockdown cells, we analyzed Epstein-Barr virus-transformed lymphoblast cells (LCLs) derived from two patients with SDS (c. 183_184TA > CT and c. 258 + 2 T > C). After 3 days of culture, the growth of LCL-SDS cell lines was considerably less than that of control donor cells. By annealing control primer-based GeneFishing PCR screening, we found that galectin-1 (Gal-1) mRNA expression was elevated in LCL-SDS cells. Western blot analysis showed that the level of Gal-1 protein expression was also increased in LCL-SDS cells as well as in SBDS-knockdown 32Dcl3 murine myeloid cells. We confirmed that recombinant Gal-1 inhibited the proliferation of both LCL-control and LCL-SDS cells and induced apoptosis (as determined by annexin V-positive staining). These results suggest that the overexpression of Gal-1 contributes to abnormal cell growth in SBDS-deficient cells., (© 2024. Japanese Society of Hematology.)

Background: Multisystemic findings of inherited bone marrow failure syndromes may cause difficulty in diagnosis. Exome sequencing (ES) helps to define the etiology of rare diseases and reanalysis offers a valuable new diagnostic approach. Herein, we present the clinical and molecular characteristics of a girl who was referred for cytopenia and frequent infections., Case Report: A 5-year-old girl with cytopenia, dysmorphism, short stature, developmental delay, and myopia was referred for genetic counseling. Reanalysis of the ES data revealed a homozygous splice-site variant in the DNAJC21 (NM_001012339.3:c.983+1G>A), causing Shwachman-Diamond Syndrome (SDS). It was shown by the RNA sequencing that exon 7 was skipped, causing an 88-nucleotide deletion., Conclusions: Precise genetic diagnosis enables genetic counseling and improves patient management by avoiding inappropriate treatment and unnecessary testing. This report would contribute to the clinical and molecular understanding of this rare type of SDS caused by DNAJC21 variants and expand the phenotypic features of this condition., Competing Interests: The authors have no conflicts of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Introduction: The inherited bone marrow failure syndromes (IBMFSs) are a group of rare disorders characterized by bone marrow failure (BMF), physical abnormalities, and an increased risk of neoplasia. The National Institute of Pediatrics (INP) is a major medical institution in Mexico, where patients with BMF receive a complete approach that includes paraclinical tests. Readily recognizable features, such as the hematological and distinctive physical phenotypes, identified by clinical dysmorphologists, remain crucial for the diagnosis and management of these patients, particularly in circumstances where next-generation sequencing (NGS) is not easily available. Here, we describe a group of Mexican patients with a high clinical suspicion of an IBMFS. Methods: We performed a systematic retrospective analysis of the medical records of patients who had a high IBMFS suspicion at our institution from January 2018 to July 2021. An initial assessment included first ruling out acquired causes of BMF by the Hematology Department and referral of the patient to the Department of Human Genetics for physical examination to search for specific phenotypes suggesting an IBMFS. Patients with high suspicion of having an IBMFS were classified into two main groups: 1) specific IBMFS , including dyskeratosis congenita (DC), Diamond-Blackfan anemia (DBA), Shwachman-Diamond syndrome (SDS), thrombocytopenia with absent radii (TAR), and severe congenital neutropenia (SCN); 2) undefined IBMFS (UI). Results: We established a high suspicion of having an IBMFS in 48 patients. At initial evaluation, the most common hematologic features were bicytopenia (20%) and aplastic anemia (16%); three patients received hematopoietic stem cell transplantation. Among patients with a suspicion of an IBMFS, the most common physical abnormality was minor craniofacial features in 83% of patients and neurodevelopmental disorders in 52%. The specific suspicions that we built were DBA (31%), SDS (18%), DC (14%), TAR (4%), and SCN (4%), whereas 27% of cases remained as undefined IBMFS. SDS, TAR, and SCN were more commonly suspected at an earlier age (<1 year), followed by DBA (2 years) and DC (5 years). Conclusions: Thorough examination of reported clinical data allowed us to highly suspect a specific IBMFS in approximately 70% of patients; however, an important number of patients remained with suspicion of an undefined IBMFS. Implementation of NGS and telomere length measurement are forthcoming measures to improve IBMFS diagnosis in Mexico., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Leal-Anaya, Kimball, Yanez-Felix, Fiesco-Roa, García-de Teresa, Monsiváis, Juárez-Velázquez, Lieberman, Villarroel, Yokoyama, Fernández-Hernández, Rivera-Osorio, Sosa, Ortiz Sandoval, López-Santiago, Frías, Castillo and Rodríguez.)

Shwachman-Diamond syndrome (SDS) is an autosomal recessive disease caused by mutation in the Shwachman-Bodian-Diamond syndrome (SBDS) gene. SDS has a variety of clinical features, including exocrine pancreatic insufficiency and hematological dysfunction. Neutropenia is the most common symptom in patients with SDS. SDS is also associated with an elevated risk of developing myelodysplastic syndromes and acute myeloid leukemia. The SBDS protein is involved in ribosome biogenesis, ribosomal RNA metabolism, stabilization of mitotic spindles and cellular stress responses, yet the function of SBDS in detail is still incompletely understood. Considering the diverse function of SBDS, the effect of SBDS seems to be different in different cells and tissues. In this study, we established myeloid cell line 32Dcl3 with a common pathogenic SBDS variant on both alleles in intron 2, 258 + 2T > C, and examined the cellular damage that resulted. We found that the protein synthesis was markedly decreased in the mutant cells. Furthermore, reactive oxygen species (ROS) production was increased, and oxidation of the mitochondrial membrane lipids and DNA damage were induced. These findings provide new insights into the cellular and molecular pathology caused by SBDS deficiency in myeloid cells.

Shwachman-Diamond syndrome (SDS) is characterized by neutropenia, exocrine pancreatic insufficiency and skeletal abnormalities. SDS bone marrow haematopoietic progenitors show increased apoptosis and impairment in granulocytic differentiation. Loss of Shwachman-Bodian-Diamond syndrome (SBDS) expression results in reduced eukaryotic 80S ribosome maturation. Biallelic mutations in the SBDS gene are found in ~90% of SDS patients, ~55% of whom carry the c.183-184TA>CT nonsense mutation. Several translational readthrough-inducing drugs aimed at suppressing nonsense mutations have been developed. One of these, ataluren, has received approval in Europe for the treatment of Duchenne muscular dystrophy. We previously showed that ataluren can restore full-length SBDS protein synthesis in SDS-derived bone marrow cells. Here, we extend our preclinical study to assess the functional restoration of SBDS capabilities in vitro and ex vivo. Ataluren improved 80S ribosome assembly and total protein synthesis in SDS-derived cells, restored myelopoiesis in myeloid progenitors, improved neutrophil chemotaxis in vitro and reduced neutrophil dysplastic markers ex vivo. Ataluren also restored full-length SBDS synthesis in primary osteoblasts, suggesting that its beneficial role may go beyond the myeloid compartment. Altogether, our results strengthened the rationale for a Phase I/II clinical trial of ataluren in SDS patients who harbour the nonsense mutation., (© 2023 The Authors. British Journal of Haematology published by British Society for Haematology and John Wiley & Sons Ltd.)

Background: Shwachman-Diamond syndrome (SDS) is an autosomal recessive disease which results in inherited bone marrow failure (IBMF) and is characterized by exocrine pancreatic dysfunction and diverse clinical phenotypes. In the present study, we reviewed the internationally published reports on SDS patients, in order to summarize the clinical features, epidemiology, and treatment of SDS., Methods: We searched the WangFang and China National Knowledge Infrastructure databases with the keywords "Shwachman-Diamond syndrome," "SDS," "SBDS gene" and "inherited bone marrow failure" for relevant articles published from January 2002 to October 2022. In addition, studies published from January 2002 to October 2022 were searched from the Web of Science, PubMed, and MEDLINE databases, using "Shwachman-diamond syndrome" as the keyword. Finally, one child with SDS treated in Tongji Hospital was also included., Results: The clinical features of 156 patients with SDS were summarized. The three major clinical features of SDS were found to be peripheral blood cytopenia (96.8%), exocrine pancreatic dysfunction (83.3%), and failure to thrive (83.3%). The detection rate of SDS mutations was 94.6% (125/132). Mutations in SBDS, DNAJC21, SRP54, ELF6, and ELF1 have been reported. The male-to-female ratio was approximately 1.3/1. The median age of onset was 0.16 years, but the diagnostic age lagged by a median age of 1.3 years., Conclusions: Pancreatic exocrine insufficiency and growth failure were common initial symptoms. SDS onset occurred early in childhood, and individual differences were obvious. Comprehensive collection and analysis of case-related data can help clinicians understand the clinical characteristics of SDS, which may improve early diagnosis and promote effective clinical intervention., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Shwachman-Diamond syndrome is a rare inherited bone marrow failure syndrome characterized by neutropenia, exocrine pancreatic insufficiency, and skeletal abnormalities. In 10-30% of cases, transformation to a myeloid neoplasm occurs. Approximately 90% of patients have biallelic pathogenic variants in the SBDS gene located on human chromosome 7q11. Over the past several years, pathogenic variants in three other genes have been identified to cause similar phenotypes; these are DNAJC21, EFL1, and SRP54. Clinical manifestations involve multiple organ systems and those classically associated with the Shwachman-Diamond syndrome (bone, blood, and pancreas). Neurocognitive, dermatologic, and retinal changes may also be found. There are specific gene-phenotype differences. To date, SBDS, DNAJC21, and SRP54 variants have been associated with myeloid neoplasia. Common to SBDS, EFL1, DNAJC21, and SRP54 is their involvement in ribosome biogenesis or early protein synthesis. These four genes constitute a common biochemical pathway conserved from yeast to humans that involve early stages of protein synthesis and demonstrate the importance of this synthetic pathway in myelopoiesis.

Inherited bone marrow failure syndromes (IBMFSs) include Fanconi anemia, Diamond-Blackfan anemia, Shwachman-Diamond syndrome, dyskeratosis congenita, severe congenital neutropenia, and other rare entities such as GATA2 deficiency and SAMD9/9L mutations. The IBMFS monogenic disorders were first recognized by their phenotype. Exome sequencing has validated their classification, with clusters of gene mutations affecting DNA damage response (Fanconi anemia), ribosome structure (Diamond-Blackfan anemia), ribosome assembly (Shwachman-Diamond syndrome), or telomere maintenance/stability (dyskeratosis congenita). The pathogenetic mechanisms of IBMFSs remain to be characterized fully, but an overarching hypothesis states that different stresses elicit TP53-dependent growth arrest and apoptosis of hematopoietic stem, progenitor, and precursor cells. Here, we review the IBMFSs and propose a role for pro-inflammatory cytokines, such as TGF-β, IL-1β, and IFN-α, in mediating the cytopenias. We suggest a pathogenic role for cytokines in the transformation to myeloid neoplasia and hypothesize a role for anti-inflammatory therapies.

Background: Shwachman-Diamond syndrome (SDS) is a rare congenital disorder caused by mutations in the SBDS gene and characterized by exocrine pancreatic deficiency, hematologic dysfunction, and skeletal growth failure. Although the hematologic features and characteristics of the somatic disorders commonly associated with SDS are well known, emerging data from case reports and patient registries suggest that SDS may also be associated with an increased risk of diabetes mellitus. However, currently available data on SDS-associated diabetes are limited and do not allow conclusions regarding prevalence and incidence rates, clinical course, and outcomes., Case Presentation: Here we report the case of a 5-year-old girl with SDS who underwent bone marrow transplantation at the age of 3 months and developed autoantibody-positive type 1 diabetes mellitus at the age of 1.8 years. The manifestation and course of diabetes development were mild, complicated by concurrent spontaneous episodes of hypoglycemia even before the onset of antidiabetic treatment. Currently, adequate metabolic control can be achieved by dietary intervention., Conclusions: Considering that the SBDS protein regulates mitosis and ribosomal biosynthesis and that its suppression may cause immunologic instability and chronic inflammation, this case provides insight into the phenotype of rare Shwachman-Diamond syndrome-associated diabetes mellitus, which may be characterized by significant age-dependent differences in clinical course., (© 2023. Società Italiana di Pediatria.)

Shwachman-Diamond syndrome (SDS) is an inherited multisystem ribosomopathy characterized by exocrine pancreatic deficiency, bone marrow failure, and predisposition to myeloid malignancies. The pathobiology of SDS results from impaired ribosomal maturation due to the deficiency of SBDS and the inability to evict the antiassociation factor eIF6 from the 60S ribosomal subunit. Clinical outcomes for patients with SDS who develop myeloid malignancies are extremely poor because of high treatment-related toxicities and a high rate of refractory disease/relapse even after allogeneic hematopoietic stem cell transplant (HSCT). Registry data indicate that outcomes are improved for patients with SDS who undergo routine bone marrow surveillance and receive an HSCT before developing an overt malignancy. However, the optimal approach to hematologic surveillance and the timing of HSCT for patients with SDS is not clearly established. Recent studies have elucidated distinct patterns of somatic blood mutations in patients with SDS that either alleviate the ribosome defect via somatic rescue (heterozygous EIF6 inactivation) or disrupt cellular checkpoints, resulting in increased leukemogenic potential (heterozygous TP53 inactivation). Genomic analysis revealed that most myeloid malignancies in patients with SDS have biallelic loss-of-function TP53 mutations. Single-cell DNA sequencing of SDS bone marrow samples can detect premalignant biallelic TP53-mutated clones before clinical diagnosis, suggesting that molecular surveillance may enhance the detection of incipient myeloid malignancies when HSCT may be most effective. Here, we review the clinical, genetic, and biologic features of SDS. In addition, we present evidence supporting the hematologic surveillance for patients with SDS that incorporates clinical, pathologic, and molecular data to risk stratify patients and prioritize transplant evaluation for patients with SDS with high-risk features., (© 2023 by The American Society of Hematology. Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution. All other rights reserved.)

The Shwachman-Diamond syndrome (SDS) is a rare inherited ribosomopathy that is predominantly caused by mutations in the Shwachman-Bodian-Diamond Syndrome gene (SBDS). SBDS is a ribosomal maturation factor that is essential for the release of eukaryotic translation initiation factor 6 (eIF6) from 60S ribosomal subunits during the late stages of 60S maturation. Release of eIF6 is critical to permit inter-subunit interactions between the 60S and 40S subunits and to form translationally competent 80S monosomes. SBDS has three key domains that are highly flexible and adopt varied conformations in solution. To better understand the domain dynamics of SBDS upon binding to 60S and to assess the effects of SDS-disease specific mutations, we aimed to site-specifically label individual domains of SBDS. Here we detail the generation of a fluorescently labeled SBDS to monitor the dynamics of select domains upon binding to 60S. We describe the incorporation of 4-azido-l-phenylalanine (4AZP), a noncanonical amino acid in human SBDS. Site-specific labeling of SBDS using fluorophore and assessment of 60S binding activity are also described. Such labeling approaches to capture the interactions of individual domains of SBDS with 60S are also applicable to study the dynamics of other multi-domain proteins that interact with the ribosomal subunits., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Shwachman-Diamond syndrome (SDS) represents one of the most common inherited bone marrow failure syndromes and is mainly caused by SBDS gene mutations. Only supportive treatments are available, with hematopoietic cell transplantation required when marrow failure occurs. Among all causative mutations, the SBDS c.258+2T>C variant at the 5' splice site (ss) of exon 2 is one of the most frequent. Here, we investigated the molecular mechanisms underlying aberrant SBDS splicing and showed that SBDS exon 2 is dense in splicing regulatory elements and cryptic splice sites, complicating proper 5'ss selection. Studies ex vivo and in vitro demonstrated that the mutation alters splicing, but it is also compatible with tiny amounts of correct transcripts, which would explain the survival of SDS patients. Moreover, for the first time for SDS, we explored a panel of correction approaches at the RNA and DNA levels and provided experimental evidence that the mutation effect can be partially counteracted by engineered U1snRNA, trans-splicing, and base/prime editors, ultimately leading to correctly spliced transcripts (from barely detectable to 2.5-5.5%). Among them, we propose DNA editors that, by stably reverting the mutation and potentially conferring positive selection to bone-marrow cells, could lead to the development of an innovative SDS therapy.

Shwachman-Diamond syndrome is a rare disorder that can develop malignant and nonmalignant hematological complications. Overall, 10% to 20% of Shwachman-Diamond patients need hematopoietic stem cell transplantation (HSCT), but most centers have a limited experience and different approaches. The European Society for Blood and Marrow Transplantation-Severe Aplastic Anaemia Working Party promoted an expert consensus to propose recommendations regarding key issues in the management of Shwachman-Diamond patients with hematological complications. The main items identified as relevant for improving survival were: the importance of regular and structured hematologic follow-up, the potential reduction of transplant-related mortality by using reduced-intensity conditioning regimens, the limitation of total body irradiation, particularly for non-malignant severe cytopenia/bone marrow failure, the early diagnosis of clonal malignant evolution and early recognition of an indication for HSCT. Finally, the poor results of HSCT in patients with acute myeloid leukemia, irrespective of cytoreductive chemotherapy treatment received prior to transplantation, highlights the need for innovative approaches. © 2023 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved., (Copyright © 2022 The American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc. All rights reserved.)

Background: Shwachman-Diamond syndrome (SDS) is a multisystem disorder characterized by exocrine pancreatic insufficiency and bone marrow failure. There is considerable variation in the phenotypes of SDS. We present a case of an infant presenting with SDS and left-sided ptosis., Observation: We report a case of an infant who presented with 2 episodes of severe sepsis and cytopenia, without overt symptoms of exocrine pancreatic deficiency or skeletal abnormalities. Persistent left-sided ptosis was noted in both presentations. Genetic testing confirmed the diagnosis of SDS. The left-sided ptosis was diagnosed as congenital myogenic ptosis., Conclusion: The association of ptosis and other congenital bone marrow failure syndromes is well established, but this is the first description of SDS with ptosis. This association may expand our understanding of SDS phenotypes if similar cases are reported in the future., Competing Interests: The authors declare no conflict of interest., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Introduction. Shwachman-Diamond Syndrome (SDS) is an autosomal-recessive disorder characterized by neutropenia, pancreatic exocrine insufficiency, skeletal dysplasia, and an increased risk for leukemic transformation. Biallelic mutations in the SBDS gene have been found in about 90% of patients. The clinical spectrum of SDS in patients is wide, and variability has been noticed between different patients, siblings, and even within the same patient over time. Herein, we present two SDS siblings (UPN42 and UPN43) carrying the same SBDS mutations and showing relevant differences in their phenotypic presentation. Study aim. We attempted to understand whether other germline variants, in addition to SBDS, could explain some of the clinical variability noticed between the siblings. Methods. Whole-exome sequencing (WES) was performed. Human Phenotype Ontology (HPO) terms were defined for each patient, and the WES data were analyzed using the eVai and DIVAs platforms. Results. In UPN43, we found and confirmed, using Sanger sequencing, a novel de novo variant (c.10663G > A, p.Gly3555Ser) in the KMT2A gene that is associated with autosomal-dominant Wiedemann−Steiner Syndrome. The variant is classified as pathogenic according to different in silico prediction tools. Interestingly, it was found to be related to some of the HPO terms that describe UPN43. Conclusions. We postulate that the KMT2A variant found in UPN43 has a concomitant and co-occurring clinical effect, in addition to SBDS mutation. This dual molecular effect, supported by in silico prediction, could help to understand some of the clinical variations found among the siblings. In the future, these new data are likely to be useful for personalized medicine and therapy for selected cases.

The Shwachman-Diamond Syndrome (SDS) is an autosomal recessive disease whose majority of patients display mutations in a ribosome assembly protein named Shwachman-Bodian-Diamond Syndrome protein (SBDS). A specific therapy for treating this rare disease is missing, due to the lack of knowledge of the molecular mechanisms responsible for its pathogenesis. Starting from the observation that SBDS single-point mutations, localized in different domains of the proteins, are responsible for an SDS phenotype, we carried out the first comparative Molecular Dynamics simulations on three SBDS mutants, namely R19Q, R126T and I212T. The obtained 450-ns long trajectories were compared with those returned by both the open and closed forms of wild type SBDS and strongly indicated that two distinct conformations (open and closed) are both necessary for the proper SBDS function, in full agreement with recent experimental observations. Our study supports the hypothesis that the SBDS function is governed by an allosteric mechanism involving domains I and III and provides new insights into SDS pathogenesis, thus offering a possible starting point for a specific therapeutic option.

Because they can experience neutropenia due to bone marrow failure, patients with Shwachman-Diamond syndrome (SDS) carry increased risk for serious infections compared with the general population; however, there has been a paucity of data on the incidence and severity of coronavirus disease 2019 (COVID-19) in patients with SDS. We compiled results from a survey distributed to participants in the SDS Registry in May-June 2021. In this report, we describe the characteristics and outcomes of patients with SDS who had COVID-19. Patients reported a short clinical course without significant complications or cytopenias. Additionally, COVID-19 vaccines were well tolerated with minor side effects., (© 2022 Wiley Periodicals LLC.)

Inherited bone marrow failure syndrome (IBMFS) is a group of clinically heterogeneous disorders characterized by significant hematological cytopenias of one or more hematopoietic cell lineages and is associated with an increased risk of cancer. The genetic etiology of IBMFS includes germline mutations impacting several key biological processes, such as DNA repair, telomere biology, and ribosome biogenesis, which may cause four major syndromes: Fanconi anemia, dyskeratosis congenita, Diamond-Blackfan anemia, and Shwachman-Diamond syndrome. Although the clinical features of some patients may be typical of a particular IBMFS, overlapping and atypical clinical manifestations and variable penetrance pose diagnostic challenges. Here, we review the clinical and genetic features of the major forms of IBMFS and discuss their molecular genetic diagnosis. Next-generation sequencing-based gene panel testing or whole exome sequencing will help elucidate the genetic causes and underlying mechanisms of this genetically heterogeneous group of diseases.

Protein synthesis is a cyclical process consisting of translation initiation, elongation, termination and ribosome recycling. The release factors SBDS and EFL1-both mutated in the leukemia predisposition disorder Shwachman-Diamond syndrome - license entry of nascent 60S ribosomal subunits into active translation by evicting the anti-association factor eIF6 from the 60S intersubunit face. We find that in mammalian cells, eIF6 holds all free cytoplasmic 60S subunits in a translationally inactive state and that SBDS and EFL1 are the minimal components required to recycle these 60S subunits back into additional rounds of translation by evicting eIF6. Increasing the dose of eIF6 in mice in vivo impairs terminal erythropoiesis by sequestering post-termination 60S subunits in the cytoplasm, disrupting subunit joining and attenuating global protein synthesis. These data reveal that ribosome maturation and recycling are dynamically coupled by a mechanism that is disrupted in an inherited leukemia predisposition disorder., (© 2022. The Author(s).)

Shwachman-Diamond syndrome (SDS) is an autosomal recessive inherited disorder characterized by bone marrow failure, exocrine pancreatic dysfunction, and skeletal abnormalities. SDS is typically caused by a pathogenic mutation in the Shwachman-Bodian-Diamond Syndrome (SBDS) gene. Patients with SDS have an increased risk of developing acute myeloid leukemia (AML) and myelodysplastic syndromes. We identified germline biallelic SBDS mutations (p.K62X and p.I167M) in a 50-year-old AML patient who had never experienced the typical symptoms of SDS. The K62X mutation is one of the most common pathogenic mutations, whereas the significance of the I167M mutation was unclear. Based on cellular experiments, we concluded that the I167M mutation contributed to the development of AML, and chemotherapy including topoisomerase inhibitors, which induce DNA double-strand breaks, may have been toxic to this patient. Our experience indicates that some asymptomatic Shwachman-Bodian-Diamond syndrome mutations contribute to the development of leukemia, and that careful treatment selection may be warranted for patients harboring these mutations., (© 2021. Japanese Society of Hematology.)

Shwachman-Diamond syndrome (SDS) is an inherited bone marrow failure syndrome with leukemia predisposition. An understanding of the hematologic complications of SDS with age could guide clinical management, but data are limited for this rare disease. We conducted a cohort study of 153 subjects from 143 families with confirmed biallelic SBDS mutations enrolled on the North American Shwachman Diamond Registry or Bone Marrow Failure Registry. The SBDS c.258 + 2T>C variant was present in all but 1 patient. To evaluate the association between blood counts and age, 2146 blood counts were analyzed for 119 subjects. Absolute neutrophil counts were positively associated with age (P < .0001). Hemoglobin was also positively associated with age up to 18 years (P < .0001), but the association was negative thereafter (P = .0079). Platelet counts and marrow cellularity were negatively associated with age (P < .0001). Marrow cellularity did not correlate with blood counts. Severe marrow failure necessitating transplant developed in 8 subjects at a median age of 1.7 years (range, 0.4-39.5), with 7 of 8 requiring transplant prior to age 8 years. Twenty-six subjects (17%) developed a myeloid malignancy (16 myelodysplasia and 10 acute myeloid leukemia) at a median age of 12.3 years (range, 0.5-45.0) and 28.4 years (range, 14.4-47.3), respectively. A lymphoid malignancy developed in 1 patient at the age of 16.9 years. Hematologic complications were the major cause of mortality (17/20 deaths; 85%). These data inform surveillance of hematologic complications in SDS., (© 2022 by The American Society of Hematology. Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution. All other rights reserved.)

A 21-year-old man presented with bone marrow failure, short stature, fatty degeneration of the pancreas on CT images, and Shwachman-Bodian-Diamond syndrome (SBDS) gene abnormalities (exon 2: c.258+2T>C and deletion of exon 3). Thus, the patient was diagnosed with Shwachman-Diamond syndrome (SDS). In the clinical course, the patient developed acute myeloid leukemia (AML). Hematopoietic stem cell transplantation from the human-leukocytic-antigen-haploidentical father of the patient was performed. The patient was conditioned with 150 mg/m 2 fludarabine, 6.4 mg/kg busulfan, and 4 Gy total body irradiation. Graft-versus-host disease prophylaxis included tacrolimus, micophenolate mofetil, and posttransplant cyclophosphamide. Although the patient achieved a complete remission on day 21, AML relapsed on day 434 after the transplantation. He died of sepsis. The prognosis of patients with SDS and AML is poor. Adult-onset cases must be recognized, and transplantation should be performed during bone marrow failure.

Background: An isochromosome of the long arm of chromosome 7, i(7)(q10), and an interstitial deletion of the long arm of chromosome 20, del(20)(q), are the most frequent anomalies in the bone marrow of patients with Shwachman-Diamond syndrome, which is caused in most cases by mutations of the SBDS gene. These clonal changes imply milder haematological symptoms and lower risk of myelodysplastic syndromes and acute myeloid leukaemia, thanks to already postulated rescue mechanisms., Results: Bone marrow from fourteen patients exhibiting either the i(7)(q10) or the del(20)(q) and coming from two large cohorts of patients, were subjected to chromosome analyses, Fluorescent In Situ Hybridization with informative probes and array-Comparative Genomic Hybridization. One patient with the i(7)(q10) showed a subsequent clonal rearrangement of the normal chromosome 7 across years. Four patients carrying the del(20)(q) evolved further different del(20)(q) independent clones, within a single bone marrow sample, or across sequential samples. One patient with the del(20)(q), developed a parallel different clone with a duplication of chromosome 3 long arm. Eight patients bore the del(20)(q) as the sole chromosomal abnormality. An overall overview of patients with the del(20)(q), also including cases already reported, confirmed that all the deletions were interstitial. The loss of material varied from 1.7 to 26.9 Mb and resulted in the loss of the EIF6 gene in all patients., Conclusions: Although the i(7)(q) and the del(20)(q) clones are frequent and clinically benign in Shwachman Diamond-syndrome, in the present work we show that they may rearrange, may be lost and then reconstructed de novo, or may evolve with independent clones across years. These findings unravel a striking selective pressure exerted by SBDS deficiency driving to karyotype instability and to specific clonal abnormalities., (© 2021. The Author(s).)

Competing Interests: Declaration of competing interest The author declares no conflict of interest.

Shwachman-Diamond syndrome with Shwachman-Bodian-Diamond syndrome (SBDS) biallelic variants is a rare disorder that predisposes the carrier to malignant hemopathies but solid-cancer predisposition is poorly known. Among 155 cases entered in the French Registry for Severe Chronic Neutropenia, three were identified with malignant solid tumors (ovary, breast, and esophagus). All cancers occurred during the fifth decade and, despite being localized at diagnosis, were rapidly fatal thereafter. No cancer was observed post transplantation in the 14 HSCT survivors. Based on the literature and our patient data, we can merely advance that this complication is predominantly diagnosed in adults., (© 2021 Wiley Periodicals LLC.)