Investigation of HLA susceptibility alleles and genotypes with hematological disease among Chinese Han population.

Several genes involved in the pathogenesis have been identified, with the human leukocyte antigen (HLA) system playing an essential role. However, the relationship between HLA and a cluster of hematological diseases has received little attention in China. Blood samples (n = 123913) from 43568 patients and 80345 individuals without known pathology were genotyped for HLA class I and II using sequencing-based typing. We discovered that HLA-A*11:01, B*40:01, C*01:02, DQB1*03:01, and DRB1*09:01 were prevalent in China. Furthermore, three high-frequency alleles (DQB1*03:01, DQB1*06:02, and DRB1*15:01) were found to be hazardous in malignant hematologic diseases when compared to controls. In addition, for benign hematologic disorders, 7 high-frequency risk alleles (A*01:01, B*46:01, C*01:02, DQB1*03:03, DQB1*05:02, DRB1*09:01, and DRB1*14:54) and 8 high-frequency susceptible genotypes (A*11:01-A*11:01, B*46:01-B*58:01, B*46:01-B*46:01, C*01:02-C*03:04, DQB1*03:01-DQB1*05:02, DQB1*03:03-DQB1*06:01, DRB1*09:01-DRB1*15:01, and DRB1*14:54-DRB1*15:01) were observed. To summarize, our findings indicate the association between HLA alleles/genotypes and a variety of hematological disorders, which is critical for disease surveillance.

RNA therapeutics for the treatment of blood disorders.

Blood disorders are defined as diseases related to the structure, function, and formation of blood cells. These diseases lead to increased years of life loss, reduced quality of life, and increased financial burden for social security systems around the world. Common blood disorder treatments such as using chemical drugs, organ transplants, or stem cell therapy have not yet approached the best goals, and treatment costs are also very high. RNA with a research history dating back several decades has emerged as a potential method to treat hematological diseases. A number of clinical trials have been conducted to pave the way for the use of RNA molecules to cure blood disorders. This novel approach takes advantage of regulatory mechanisms and the versatility of RNA-based oligonucleotides to target genes and cellular pathways involved in the pathogenesis of specific diseases. Despite positive results, currently, there is no RNA drug to treat blood-related diseases approved or marketed. Before the clinical adoption of RNA-based therapies, challenges such as safe delivery of RNA molecules to the target site and off-target effects of injected RNA in the body need to be addressed. In brief, RNA-based therapies open novel avenues for the treatment of hematological diseases, and clinical trials for approval and practical use of RNA-targeted are crucial.

Next generation phenotyping for diagnosis and phenotype-genotype correlations in Kabuki syndrome.

The field of dysmorphology has been changed by the use Artificial Intelligence (AI) and the development of Next Generation Phenotyping (NGP). The aim of this study was to propose a new NGP model for predicting KS (Kabuki Syndrome) on 2D facial photographs and distinguish KS1 (KS type 1, KMT2D-related) from KS2 (KS type 2, KDM6A-related). We included retrospectively and prospectively, from 1998 to 2023, all frontal and lateral pictures of patients with a molecular confirmation of KS. After automatic preprocessing, we extracted geometric and textural features. After incorporation of age, gender, and ethnicity, we used XGboost (eXtreme Gradient Boosting), a supervised machine learning classifier. The model was tested on an independent validation set. Finally, we compared the performances of our model with DeepGestalt (Face2Gene). The study included 1448 frontal and lateral facial photographs from 6 centers, corresponding to 634 patients (527 controls, 107 KS); 82 (78%) of KS patients had a variation in the KMT2D gene (KS1) and 23 (22%) in the KDM6A gene (KS2). We were able to distinguish KS from controls in the independent validation group with an accuracy of 95.8% (78.9-99.9%, p < 0.001) and distinguish KS1 from KS2 with an empirical Area Under the Curve (AUC) of 0.805 (0.729-0.880, p < 0.001). We report an automatic detection model for KS with high performances (AUC 0.993 and accuracy 95.8%). We were able to distinguish patients with KS1 from KS2, with an AUC of 0.805. These results outperform the current commercial AI-based solutions and expert clinicians.

Attention challenges in Kabuki syndrome.

BACKGROUND: Understanding the specific neurobehavioural profile of rare genetic diseases enables clinicians to provide the best possible care for patients and families, including prognostic and treatment advisement. Previous studies suggested that a subset of individuals with Kabuki syndrome (KS), a genetic disorder causing intellectual disability and other neurodevelopmental phenotypes, have attentional deficits. However, these studies looked at relatively small numbers of molecularly confirmed cases and often used retrospective clinical data instead of standardised assessments. METHODS: Fifty-five individuals or caregivers of individuals with molecularly confirmed KS completed assessments to investigate behaviour and adaptive function. Additionally, information was collected on 23 unaffected biological siblings as controls. RESULTS: Attention Problems in children was the only behavioural category that, when averaged, was clinically significant, with the individual scores of nearly 50% of the children with KS falling in the problematic range. Children with KS scored significantly higher than their unaffected sibling on nearly all behavioural categories. A significant correlation was found between Attention Problems scores and adaptive function scores (P = 0.032), which was not explained by lower general cognitive ability. CONCLUSIONS: We found that the rates of children with attentional deficits are much more elevated than would be expected in the general population, and that attention challenges are negatively correlated with adaptive function. When averaged across KS participants, none of the behavioural categories were in the clinically significant range except Attention Problems for children, which underscores the importance of clinicians screening for attention deficit hyperactivity disorder (ADHD) in children with KS.

Neonatal Kabuki syndrome caused by KMT2D mutation: A case report.

BACKGROUND: Kabuki syndrome (KS) is an autosomal dominant inherited syndrome that involves multiple organs and systems. Gene mutation is the main cause of KS. The reported mutations in X-linked histone H3 lysine 4 methylase (KMT2D) and KDM6A genes are 2 relatively clear pathogenic pathways. In this paper, we report a case of KS with neonatal hypoglycemia and special features caused by KMT2D gene mutation confirmed by whole exome sequencing, it enriched the clinical phenotype spectrum and gene mutation spectrum of KS, which helps to improve the understanding of the disease. CASE REPORT: Through whole exome sequencing, we performed gene diagnosis of a newborn child with special facial features and multiple malformations, which revealed heterozygous mutation of NM_003482.3:c.755dupA(p.His252Glnfs*21) in KMT2D gene. It is consistent with the pathogenesis of KS, an autosomal dominat genetic disease caused by KMT2D gene mutation. This pathogenic mutation has not been prebiously reported. DISCUSSION: KS has strong clinical characteristics and biological heterogeneity. Genetic diagnosis can help identify mutant gene types. However, the relationship between genotype and phenotype has not been fully clarified. The molecular etiological mechanism still needs to be further explored and elucidated.

CRISPR-based precision medicine for hematologic disorders: Advancements, challenges, and prospects.

The development of programmable nucleases to introduce defined alterations in genomic sequences has been a powerful tool for precision medicine. While several nucleases such as zinc-finger nucleases (ZFN), transcriptor activator-like effector nucleases (TALEN), and meganucleases have been explored, the advent of CRISPR/Cas9 technology has revolutionized the field of genome engineering. In addition to disease modeling, the CRISPR/Cas9 technology has contributed to safer and more effective treatment strategies for hematologic diseases and personalized T-cell-based therapies. Here we discuss the applications of the CRISPR technology in the treatment of hematologic diseases, their efficacy, and ongoing clinical trials. We examine the obstacles to their successful use and the approaches investigated to overcome these challenges. Finally, we provide our perspectives to improve this genome editing tool for targeted therapies.

The influence of methotrexate-related transporter and metabolizing enzyme gene polymorphisms on peri-engraftment syndrome and graft-versus-host disease after haplo-hematopoietic stem cell transplantation in pediatric patients with malignant hematological diseases.

Background: Methotrexate (MTX), utilized as a graft-versus-host disease (GvHD) prophylactic agent in allogeneic hematopoietic stem cell transplantation (allo-HSCT), has been proven to effectively decrease the occurrence of the peri-engraftment syndrome (Peri-ES) and acute GvHD (aGvHD). Changes in the pharmacodynamics of MTX are closely associated with gene polymorphisms in genes encoding drug-metabolizing enzymes and transporters. Nevertheless, the current studies mainly concentrate on leukemia or autoimmune diseases, and limited studies on allo-HSCT were reported. Methods: Here, we retrospectively assessed the relationship between MTX-related transporter and metabolizing enzyme gene polymorphisms, clinical characteristics, and outcomes in 57 pediatric patients who received haploid HSCT (haplo-HSCT) with malignant tumors at a single center. Results: We discovered all gene polymorphisms were in the Hardy-Weinberg equilibrium in our cohort. We discovered a significant correlation between platelet recovery time and ABCB1 (1236C>T) (p = 0.042). Compared with patients with SLCO1B1 (1865+4846T>C) TT, patients with SLCO1B1 (1865+4846T>C) TC/CC had an increased incidence of Peri-ES (p = 0.030). Based on the multivariate Cox analysis, we discovered that SLCO1B1 (1865+4846T>C) TT genotype was an independent protective factor for Peri-ES morbidity (hazard ratio (HR) = 0.464, p = 0.031), and the dose of mononuclear cells reinfused was significantly correlated with II-IV aGvHD (HR = 2.604, p = 0.039). Conclusion: In summary, our findings prove that the host's genotypes might modify the risk of developing Peri-ES, contribute to a better understanding of the inter-individual difference in efficacy, and facilitate the development of individualized approaches to GvHD prophylaxis.

Artificial Intelligence-Assisted Diagnostic Cytology and Genomic Testing for Hematologic Disorders.

Artificial intelligence (AI) is a rapidly evolving field of computer science that involves the development of computational programs that can mimic human intelligence. In particular, machine learning and deep learning models have enabled the identification and grouping of patterns within data, leading to the development of AI systems that have been applied in various areas of hematology, including digital pathology, alpha thalassemia patient screening, cytogenetics, immunophenotyping, and sequencing. These AI-assisted methods have shown promise in improving diagnostic accuracy and efficiency, identifying novel biomarkers, and predicting treatment outcomes. However, limitations such as limited databases, lack of validation and standardization, systematic errors, and bias prevent AI from completely replacing manual diagnosis in hematology. In addition, the processing of large amounts of patient data and personal information by AI poses potential data privacy issues, necessitating the development of regulations to evaluate AI systems and address ethical concerns in clinical AI systems. Nonetheless, with continued research and development, AI has the potential to revolutionize the field of hematology and improve patient outcomes. To fully realize this potential, however, the challenges facing AI in hematology must be addressed and overcome.

Exploration of KIR genes and hematological-related diseases in Chinese Han population.

The function of natural killer (NK) cells has previously been implicated in hematopoietic-related diseases. Killer immunoglobulin-like receptors (KIR) play an important role in NK cells after hematopoietic stem cell transplantation. To explore the immunogenetic predisposition of hematological-related diseases, herein, a multi-center retrospective study in China was conducted, analyzing and comparing 2519 patients with hematopathy (mainly, acute lymphoblastic leukemia, acute myeloid leukemia, aplastic anemia, and myelodysplastic syndrome) to 18,108 individuals without known pathology. Genotyping was performed by polymerase chain reaction with specific sequence primers (PCR-SSP). As a result, we discovered four genes including KIR2DL5 (OR: 0.74, 95% CI 0.59-0.93; Pc = 0.0405), 2DS1 (OR: 0.74, 95% CI 0.59-0.93; Pc = 0.0405), 2DS3 (OR: 0.58, 95% CI 0.41-0.81; Pc = 0.0180), and 3DS1 (OR: 0.74, 95% CI 0.58-0.94; Pc = 0.0405) to be protective factors that significantly reduce the risk of aplastic anemia. Our findings offer new approaches to immunotherapy for hematological-related diseases. As these therapies mature, they are promising to be used alone or in combination with current treatments to help to make blood disorders a manageable disease.

Identification of a KDM6A somatic mutation responsible for Kabuki syndrome by excluding a conflicting KMT2D germline variant through episignature analysis.

Kabuki syndrome (KS) is a congenital disorder caused by mutations in either KMT2D on chromosome 12 or KDM6A on chromosome X, encoding a lysine methyltransferase and a lysine demethylase, respectively. A 9-year-4-month-old male patient with a normal karyotype presented with KS and autism spectrum disorder. Genetic testing for KS was conducted by Sanger sequencing and episignature analysis using DNA methylation array data. The patient had a mosaic stop-gain variant in KDM6A and a heterozygous missense variant (rs201078160) in KMT2D. The KDM6A variant is expected to be deleterious. The KMT2D variant pathogenicity has been inconsistently reported in the ClinVar database. Using biobanking resources, we identified two heterozygous individuals possessing the rs201078160 variant. In a subsequent episignature analysis, the KS patient showed the KS episignature, but two control individuals with the rs201078160 variant did not. Our results indicate that the mosaic stop-gained variant in KDM6A, but not the rs201078160 variant in KMT2D, is responsible for the KS phenotype in the patient. This study further demonstrated the utility of DNA methylation information in diagnosing rare genetic diseases and emphasized the importance of a reference dataset containing both genotype and DNA methylation information.

Unmasking the challenges of Kabuki syndrome in adulthood: A case series.

Kabuki syndrome is a recognizable Mendelian disorder characterized by the clinical constellation of childhood hypotonia, developmental delay or intellectual impairment, and characteristic dysmorphism resulting from monoallelic pathogenic variants in KMT2D or KDM6A. In the medical literature, most reported patients are children, and data is lacking on the natural history of the condition across the lifespan, with little known about adult-specific presentations and symptoms. Here, we report the results of a retrospective chart review of eight adult patients with Kabuki syndrome, seven of whom are molecularly confirmed. We use their trajectories to highlight the diagnostic challenges unique to an adult population, expand on neurodevelopmental/psychiatric phenotypes across the lifespan, and describe adult-onset medical complications, including a potential cancer risk and unusual and striking premature/accelerated aging phenotype.

Comparative analysis of Tet2 catalytic-deficient and knockout bone marrow over time.

TET2 is a member of the Ten-eleven translocation (Tet) family of DNA dioxygenases that regulate gene expression by promoting DNA demethylation (enzymatic activity) and partnering with chromatin regulatory complexes (nonenzymatic functions). TET2 is highly expressed in the hematopoietic lineage, where its molecular functions are the subject of continuous investigations because of the prevalence of TET2 mutations in hematologic malignancies. Previously, we have implicated Tet2 catalytic and noncatalytic functions in the regulation of myeloid and lymphoid lineages, respectively. However, the impact of these functions of Tet2 on hematopoiesis as the bone marrow ages remains unclear. Here, we conducted comparative transplantations and transcriptomic analyses of 3-, 6-, 9-, and 12-month-old Tet2 catalytic mutant (Mut) and knockout (KO) bone marrow. Tet2 Mut bone marrow of all ages exclusively caused hematopoietic disorders of the myeloid lineage. In contrast, young Tet2 KO bone marrow developed both lymphoid and myeloid diseases, whereas older Tet2 KO bone marrow predominantly elicited myeloid disorders with shorter latency than age-matched Tet2 Mut bone marrow. We identified robust gene dysregulation in Tet2 KO Lin- cells at 6 months that involved lymphoma and myelodysplastic syndrome and/or leukemia-causing genes, many of which were hypermethylated early in life. There was a shift from lymphoid to myeloid gene deregulation in Tet2 KO Lin- cells with age, underpinning the higher incidence of myeloid diseases. These findings expand on the dynamic regulation of bone marrow by Tet2 and show that its catalytic-dependent and -independent roles have distinct impacts on myeloid and lymphoid lineages with age.

Characterizing the molecular impact of KMT2D variants on the epigenetic and transcriptional landscapes in Kabuki syndrome.

Kabuki syndrome (KS) is a rare, multisystem disorder with a variable clinical phenotype. The majority of KS is caused by dominant loss-of-function mutations in KMT2D (lysine methyltransferase 2D). KMT2D mediates chromatin accessibility by adding methyl groups to lysine residue 4 of histone 3, which plays a critical role in cell differentiation and homeostasis. The molecular underpinnings of KS remain elusive partly because of a lack of histone modification data from human samples. Consequently, we profiled and characterized alterations in histone modification and gene transcription in peripheral blood mononuclear cells (PBMCs) from 33 patients with KMT2D mutations and 36 unaffected healthy controls. Our analysis identified unique enhancer signatures in H3K4me1 and H3K4me2 in KS compared with controls. Reduced enhancer signals were present for promoter-distal sites of immune-related genes for which co-binding of PBMC-specific transcription factors was predicted; 31% of super-enhancers of normal blood cells overlapped with disrupted enhancers in KS, supporting an association of reduced enhancer activity of immune-related genes with immune deficiency phenotypes. In contrast, increased enhancer signals were observed for promoter-proximal regions of metabolic genes enriched with EGR1 and E2F2 motifs, whose transcriptional levels were significantly increased in KS. Additionally, we identified ~100 de novo enhancers in genes, such as in MYO1F and AGAP2. Together, our results underscore the effect of KMT2D haploinsufficiency on dysregulation of enhancer states and gene transcription and provide a framework for the identification of therapeutic targets and biomarkers in preparation for clinical trial readiness.

DNA methylation signature classification of rare disorders using publicly available methylation data.

Disease-specific DNA methylation patterns (DNAm signatures) have been established for an increasing number of genetic disorders and represent a valuable tool for classification of genetic variants of uncertain significance (VUS). Sample size and batch effects are critical issues for establishing DNAm signatures, but their impact on the sensitivity and specificity of an already established DNAm signature has not previously been tested. Here, we assessed whether publicly available DNAm data can be employed to generate a binary machine learning classifier for VUS classification, and used variants in KMT2D, the gene associated with Kabuki syndrome, together with an existing DNAm signature as proof-of-concept. Using publicly available methylation data for training, a classifier for KMT2D variants was generated, and individuals with molecularly confirmed Kabuki syndrome and unaffected individuals could be correctly classified. The present study documents the clinical utility of a robust DNAm signature even for few affected individuals, and most importantly, underlines the importance of data sharing for improved diagnosis of rare genetic disorders.

Epigenetic Modification of Cytosines in Hematopoietic Differentiation and Malignant Transformation.

The mammalian DNA methylation landscape is established and maintained by the combined activities of the two key epigenetic modifiers, DNA methyltransferases (DNMT) and Ten-eleven-translocation (TET) enzymes. Once DNMTs produce 5-methylcytosine (5mC), TET proteins fine-tune the DNA methylation status by consecutively oxidizing 5mC to 5-hydroxymethylcytosine (5hmC) and further oxidized derivatives. The 5mC and oxidized methylcytosines are essential for the maintenance of cellular identity and function during differentiation. Cytosine modifications with DNMT and TET enzymes exert pleiotropic effects on various aspects of hematopoiesis, including self-renewal of hematopoietic stem/progenitor cells (HSPCs), lineage determination, differentiation, and function. Under pathological conditions, these enzymes are frequently dysregulated, leading to loss of function. In particular, the loss of DNMT3A and TET2 function is conspicuous in diverse hematological disorders, including myeloid and lymphoid malignancies, and causally related to clonal hematopoiesis and malignant transformation. Here, we update recent advances in understanding how the maintenance of DNA methylation homeostasis by DNMT and TET proteins influences normal hematopoiesis and malignant transformation, highlighting the potential impact of DNMT3A and TET2 dysregulation on clonal dominance and evolution of pre-leukemic stem cells to full-blown malignancies. Clarification of the normal and pathological functions of DNA-modifying epigenetic regulators will be crucial to future innovations in epigenetic therapies for treating hematological disorders.

Insights into the perinatal phenotype of Kabuki syndrome in infants identified by genome-wide sequencing.

Increasing use of unbiased genomic sequencing in critically ill infants can expand understanding of rare diseases such as Kabuki syndrome (KS). Infants diagnosed with KS through genome-wide sequencing performed during the initial hospitalization underwent retrospective review of medical records. Human phenotype ontology terms used in genomic analysis were aggregated and analyzed. Clinicians were surveyed regarding changes in management and other care changes. Fifteen infants met inclusion criteria. KS was not suspected prior to genomic sequencing. Variants were classified as Pathogenic (n = 10) or Likely Pathogenic (n = 5) by American College of Medical Genetics and Genomics Guidelines. Fourteen variants were de novo (KMT2D, n = 12, KDM6A, n = 2). One infant inherited a likely pathogenic variant in KMT2D from an affected father. Frequent findings involved cardiovascular (14/15) and renal (7/15) systems, with palatal defects also identified (6/15). Three infants had non-immune hydrops. No minor anomalies were universally documented; ear anomalies, micrognathia, redundant nuchal skin, and hypoplastic nails were common. Changes in management were reported in 14 infants. Early use of unbiased genome-wide sequencing enabled a molecular diagnosis prior to clinical recognition including infants with atypical or rarely reported features of KS while also expanding the phenotypic spectrum of this rare disorder.

[Mouse models of hematological diseases using genome editing technology].

The impact of gene-editing technology has rapidly expanded into developmental engineering. Using this technology, gene targeting in mice can be performed within 2-3 months, which is a much shorter timespan than that required while using embryonic stem cell-based conventional methods, which require nearly two years. In addition, genome-editing technology omits several skillful laborious steps. This review describes the prominent merits of gene targeting using this recently established and still ongoing technology in the field of hematology. In addition, the experience of the authors is reviewed to identify and characterize genes involved in the loss of the long arm of chromosome 7 in myeloid malignancies and highlight the significance of establishing the mouse model of human diseases.