Rare mosaic variant of GJA1 in a patient with a neurodevelopmental disorder.

GJA1 is the causative gene for oculodentodigital dysplasia (ODDD). A novel de novo GJA1 variant, NM 000165:c263C > T [p.P88L], was identified in a mosaic state in a patient with short stature, seizures, delayed myelination, mild hearing loss, and tooth enamel hypoplasia. Although the patient exhibited severe neurodevelopmental delay, other clinical features of ODDD, including limb anomalies, were mild. This may be due to differences in the mosaic ratios in different organs.

Human leukocyte antigen-DQ risk heterodimeric haplotypes of left ventricular dysfunction in cardiac sarcoidosis: an autoimmune view of its role.

Cardiac sarcoidosis (CS) is the scarring of heart muscles by autoimmunity, leading to heart abnormalities and patients with sarcoidosis with cardiac involvements have poor prognoses. Due to the small number of patients, it is difficult to stratify all patients of CS by human leukocyte antigen (HLA) analysis. We focused on the structure of antigen-recognizing pockets in heterodimeric HLA-class II, in addition to DNA sequences, and extracted high-affinity combinations of antigenic epitopes from candidate autoantigen proteins and HLA. Four HLA heterodimer-haplotypes (DQA1*05:03/05:05/05:06/05:08-DQB1*03:01) were identified in 10 of 68 cases. Nine of the 10 patients had low left ventricular ejection fraction (< 50%). Fourteen amino-acid sequences constituting four HLA anchor pockets encoded by the HLA haplotypes were all common, suggesting DQA1*05:0X-DQB1*03:01 exhibit one group of heterodimeric haplotypes. The heterodimeric haplotypes recognized eight epitopes from different proteins. Assuming that autoimmune mechanisms might be activated by molecular mimicry, we searched for bacterial species having peptide sequences homologous to the eight epitopes. Within the peptide epitopes form the SLC25A4 and DSG2, high-homology sequences were found in Cutibacterium acnes and Mycobacterium tuberculosis, respectively. In this study, we detected the risk heterodimeric haplotypes of ventricular dysfunction in CS by searching for high-affinity HLA-class II and antigenic epitopes from candidate cardiac proteins.

Novel TRPS1 frameshift variant in tricho-rhino-phalangeal syndrome type I accompanied by zinc deficiency.

Tricho-rhino-phalangeal syndrome type I (TRPS1), caused by pathogenic variants in the transcriptional repressor GATA-binding 1 gene (TRPS1), is characterized by ectodermal and skeletal anomalies including short stature and sparse scalp hair during infancy. TRPS1 encodes a zinc finger protein transcription factor that contributes to bone homeostasis by regulating perichondral mineralization, chondrocyte proliferation, and apoptosis. Here, a male infant aged 14 months presented with sparse scalp hair, deformed nails, fused teeth, and postnatal growth retardation without neurodevelopmental disorder. As endocrinological measurements revealed low serum zinc levels, he was treated with zinc acetate hydrate, which improved his growth velocity and scalp hair. Whole-exome sequencing revealed that this patient harbored a novel pathogenic de novo heterozygous TRPS1 frameshift variant, c.2819_2822del, p.(His940Argfs*6). Zinc deficiency induces zinc finger protein dysfunction via effects on protein folding and assembly, affecting target gene transcription and apoptosis. The symptoms of TRPS1 are similar to those caused by inadequate levels of zinc, an essential trace element with important roles in tissue growth and repair. Accompanying zinc deficiency may have affected the function of important zinc finger proteins, resulting in phenotypic deterioration. Analysis of zinc metabolism in patients harboring TRPS1 variants will enhance understanding the variety of phenotypes of TRPS1.

A case of Marfanoid-progeroid-lipodystrophy syndrome: experimental proof of skipping exons and escaping nonsense-mediated decay.

We report a Japanese patient with tall stature, dolichocephaly, prominent forehead, narrow nasal ridge, mild retrognathia, subcutaneous fat reduction, bilateral entropion of both eyelids, high arched palate, long fingers, and mild hyperextensible finger joints as a case of Marfanoid-progeroid-lipodystrophy syndrome. Genetic investigation revealed a heterozygous variant NC_000015.10(NM_000138.5):c.8226+5G>A in the FBN1 gene. Skipping of exon 65 and escaping nonsense-mediated decay followed by frameshift were experimentally confirmed in the proband's mRNA.

Clinical Outcomes and Genetic Analyses of Restrictive Cardiomyopathy in Children.

BACKGROUND: Restrictive cardiomyopathy in children is rare and outcomes are very poor. However, little information is available concerning genotype-outcome correlations. METHODS: We analyzed the clinical characteristics and genetic testing, including whole exome sequencing, of 28 pediatric restrictive cardiomyopathy patients who were diagnosed from 1998 to 2021 at Osaka University Hospital in Japan. RESULTS: The median age at diagnosis (interquartile range) was 6 (2.25-8.5) years. Eighteen patients received heart transplantations and 5 patients were on the waiting list. One patient died while waiting for transplantation. Pathologic or likely-pathogenic variants were identified in 14 of the 28 (50%) patients, including heterozygous TNNI3 missense variants in 8 patients. TNNT2, MYL2, and FLNC missense variants were also identified. No significant differences in clinical manifestations and hemodynamic parameters between positive and negative pathogenic variants were detected. However, 2- and 5-year survival rates were significantly lower in patients with pathogenic variants (50% and 22%) compared with survival in patients without pathogenic variants (62% and 54%; P=0.0496, log-rank test). No significant differences were detected in the ratio of patients diagnosed at nationwide school heart disease screening program between positive and negative pathogenic variants. Patients diagnosed by school screening showed better transplant-free survival compared with patients diagnosed by heart failure symptoms (P=0.0027 in log-rank test). CONCLUSIONS: In this study, 50% of pediatric restrictive cardiomyopathy patients had pathogenic or likely-pathogenic gene variants, and TNNI3 missense variants were the most frequent. Patients with pathogenic variants showed significantly lower transplant-free survival compared with patients without pathogenic variants.

Restoration of Cardiac Myosin Light Chain Kinase Ameliorates Systolic Dysfunction by Reducing Superrelaxed Myosin.

BACKGROUND: Cardiac-specific myosin light chain kinase (cMLCK), encoded by MYLK3, regulates cardiac contractility through phosphorylation of ventricular myosin regulatory light chain. However, the pathophysiological and therapeutic implications of cMLCK in human heart failure remain unclear. We aimed to investigate whether cMLCK dysregulation causes cardiac dysfunction and whether the restoration of cMLCK could be a novel myotropic therapy for systolic heart failure. METHODS: We generated the knock-in mice (Mylk3+/fs and Mylk3fs/fs) with a familial dilated cardiomyopathy-associated MYLK3 frameshift mutation (MYLK3+/fs) that had been identified previously by us (c.1951-1G>T; p.P639Vfs*15) and the human induced pluripotent stem cell-derived cardiomyocytes from the carrier of the mutation. We also developed a new small-molecule activator of cMLCK (LEUO-1154). RESULTS: Both mice (Mylk3+/fs and Mylk3fs/fs) showed reduced cMLCK expression due to nonsense-mediated messenger RNA decay, reduced MLC2v (ventricular myosin regulatory light chain) phosphorylation in the myocardium, and systolic dysfunction in a cMLCK dose-dependent manner. Consistent with this result, myocardium from the mutant mice showed an increased ratio of cardiac superrelaxation/disordered relaxation states that may contribute to impaired cardiac contractility. The phenotypes observed in the knock-in mice were rescued by cMLCK replenishment through the AAV9_MYLK3 vector. Human induced pluripotent stem cell-derived cardiomyocytes with MYLK3+/fs mutation reduced cMLCK expression by 50% and contractile dysfunction, accompanied by an increased superrelaxation/disordered relaxation ratio. CRISPR-mediated gene correction, or cMLCK replenishment by AAV9_MYLK3 vector, successfully recovered cMLCK expression, the superrelaxation/disordered relaxation ratio, and contractile dysfunction. LEUO-1154 increased human cMLCK activity ≈2-fold in the Vmax for ventricular myosin regulatory light chain phosphorylation without affecting the Km. LEUO-1154 treatment of human induced pluripotent stem cell-derived cardiomyocytes with MYLK3+/fs mutation restored the ventricular myosin regulatory light chain phosphorylation level and superrelaxation/disordered relaxation ratio and improved cardiac contractility without affecting calcium transients, indicating that the cMLCK activator acts as a myotrope. Finally, human myocardium from advanced heart failure with a wide variety of causes had a significantly lower MYLK3/PPP1R12B messenger RNA expression ratio than control hearts, suggesting an altered balance between myosin regulatory light chain kinase and phosphatase in the failing myocardium, irrespective of the causes. CONCLUSIONS: cMLCK dysregulation contributes to the development of cardiac systolic dysfunction in humans. Our strategy to restore cMLCK activity could form the basis of a novel myotropic therapy for advanced systolic heart failure.

Craniofacial and dental characteristics of three Japanese individuals with genetically diagnosed SATB2-associated syndrome.

Craniofacial defects are one of the most frequent phenotypes in syndromic diseases. More than 30% of syndromic diseases are associated with craniofacial defects, which are important for the precise diagnosis of systemic diseases. Special AT-rich sequence-binding protein 2 (SATB2)-associated syndrome (SAS) is a rare syndromic disease associated with a wide variety of phenotypes, including intellectual disability and craniofacial defects. Among them, dental anomalies are the most frequently observed phenotype and thus becomes an important diagnostic criterion for SAS. In this report, we demonstrate three Japanese cases of genetically diagnosed SAS with detailed craniofacial phenotypes. The cases showed multiple dental problems, which have been previously reported to be linked to SAS, including abnormal crown morphologies and pulp stones. One case showed a characteristic enamel pearl at the root furcation. These phenotypes add new insights for differentiating SAS from other disorders.

Estimation of crossbridge-state during cardiomyocyte beating using second harmonic generation.

Estimation of dynamic change of crossbridge formation in living cardiomyocytes is expected to provide crucial information for elucidating cardiomyopathy mechanisms, efficacy of an intervention, and others. Here, we established an assay system to dynamically measure second harmonic generation (SHG) anisotropy derived from myosin filaments depended on their crossbridge status in pulsating cardiomyocytes. Experiments utilizing an inheritable mutation that induces excessive myosin-actin interactions revealed that the correlation between sarcomere length and SHG anisotropy represents crossbridge formation ratio during pulsation. Furthermore, the present method found that ultraviolet irradiation induced an increased population of attached crossbridges that lost the force-generating ability upon myocardial differentiation. Taking an advantage of infrared two-photon excitation in SHG microscopy, myocardial dysfunction could be intravitally evaluated in a Drosophila disease model. Thus, we successfully demonstrated the applicability and effectiveness of the present method to evaluate the actomyosin activity of a drug or genetic defect on cardiomyocytes. Because genomic inspection alone may not catch the risk of cardiomyopathy in some cases, our study demonstrated herein would be of help in the risk assessment of future heart failure.

A family with brachydactyly mental retardation syndrome with a missense variant in HDAC4.

Brachydactyly mental retardation syndrome (BDMR) or chromosome 2q37 deletion syndrome is a genetic disorder caused by 2q37 deletion or haploinsufficiency of histone deacetylase 4 (HDAC4). The HDAC4 gene is responsible for major BDMR phenotypes. The symptoms of BDMR include mild-to-moderate intellectual disability, seizures, autism spectrum disorder, short stature, obesity, and facial dysmorphism. Here, we report a family (n = 5) with BDMR who had a missense variant of HDAC4. Four affected individuals [5-yr-old girl (index case); 15- and 3-yr-old siblings; and father] had mild intellectual disability, three of the four affected individuals had short stature and mild cardiac anomalies, and two of the four affected individuals had hypothyroidism. Whole-exome sequencing and analyses of the index case and her family revealed an allelic variant in the HDAC4 gene (NM_001378414.1:c.2204G>A:p. Arg735Gln). A healthy family member (mother) did not have the missense variant. To our knowledge, this is the first report of a missense variation in HDAC4 that is associated with BDMR.

Association Between Genetic Diagnosis and Clinical Outcomes in Patients With Heritable Thoracic Aortic Disease.

Background Differences in the clinical course of heritable thoracic aortic disease based on the disease-causing gene have not been fully evaluated. To clarify the clinical relevance of causative genes in heritable thoracic aortic disease, we assessed the clinical course of patients categorized based on genetic diagnosis. Methods and Results We investigated cardiovascular events and mortality in 518 genetically diagnosed patients in 4 groups: Group 1, FBN1 (n=344); Group 2, TGFBR1, TGFBR2, SMAD3, or TGFB2 (n=74); Group 3, COL3A1 (n=60); and Group 4, ACTA2 or MYH11 (n=40). The median age at the first cardiovascular event ranged from 30.0 to 35.5 years (P=0.36). Patients with gene variants related to transforming growth factor-ß signaling had a significantly higher rate of subsequent events than those with FBN1 variants (adjusted hazard ratio, 2.33 [95% CI, 1.60-3.38]; P<0.001). Regarding the incidence of aortic dissection, there were no significant differences among the 4 groups in male patients (36.3%, 34.3%, 21.4%, and 54.2%, respectively; P=0.06). Female patients with COL3A1 variants had a significantly lower incidence than female patients in the other 3 groups (34.2%, 59.0%, 3.1%, and 43.8%, respectively; P<0.001). Conclusions Gene variants related to transforming growth factor-ß signaling are associated with a higher incidence of subsequent cardiovascular events than FBN1 variants. COL3A1 variants might be related to a lower incidence of aortic dissection than other gene variants in women only. Identifying the genetic background of patients with heritable thoracic aortic disease is important for determining appropriate treatment.

End-stage Hypertrophic Cardiomyopathy with Advanced Heart Failure in Patients Carrying MYH7 R453 Variants: A Case Series.

The MYH7 R453 variant has been identified in inherited hypertrophic cardiomyopathy (HCM) and is associated with sudden death and a poor prognosis. The detailed clinical course of HCM with the MYH7 R453 variant, from a preserved to a reduced left ventricular ejection fraction, has not been reported. We identified the MYH7 R453C and R453H variants in three patients who progressively developed advanced heart failure requiring circulatory support and summarized the clinical course and echocardiographic parameters of these patients over the years. Because of the rapid disease progression, we consider genetic screening for patients with HCM imperative for future prognosis stratification.

Novel BCL11B truncation variant in a patient with developmental delay, distinctive features, and early craniosynostosis.

Intellectual developmental disorder with dysmorphic facies, speech delay, and T-cell abnormalities (MIM # 618092) is a congenital disorder derived from pathogenic variants of the B-cell leukemia/lymphoma 11B gene (BCL11B). Several variants have been reported to date. Here, through comprehensive genomic analysis, a novel BCL11B truncation variant, NM_138576.4(BCL11B_v001): c.2439_2452dup [p.(His818Argfs*31)], was identified in a Japanese male patient with developmental delay, distinctive features, and early craniosynostosis.

Effectiveness of an online support program to help female cancer patients manage their health and illness: Protocol for a randomized controlled trial.

Background: The aim of the trial is to evaluate the effectiveness of interventions provided by online support program apps, adopting health-related quality of life (HR-QOL) scores as indicators. Methods: The design is as an open, randomized, parallel-group trial with longitudinal data collection. The subjects will be female cancer patients receiving treatment in a Japanese National Cancer Hospital. Patients assigned to the experimental group will use three apps: an app for them to monitor their own health (monitoring app), an app to assess their understanding of their diagnosis and treatment and their readiness to receive treatment (confirmation app), and an app to address mental health issues (writing app); patients assigned to the control group will use only the monitoring app. At baseline (before patients undergo cancer treatment) and three other times during the study, evaluation indicators will be obtained from three different standardized HR-QOL scales that are incorporated in the monitoring app. The study hypothesis is that at 6 months after patients' baseline health monitoring, patients in the experimental group will have improved HR-QOL as compared with patients in the control group. Conclusion: This study is based on self-regulation theory, so it is important that the online support program works in an efficient way with respect to patients finding and setting their own health-related goals and adapting their behaviors to achieve those goals. Verifying the effectiveness of the combination of the three apps will show that it is a scientifically valid approach to maintaining or improving the HR-QOL of cancer patients.

A novel nonsense variant in ARID1B causing simultaneous RNA decay and exon skipping is associated with Coffin-Siris syndrome.

Coffin-Siris syndrome (CSS) is a congenital disorder that is characterized by an absent/hypoplastic fifth distal phalanx, psychomotor developmental delay, and coarse facial features. One of the causative genes, ARID1B (AT-rich interactive domain-containing protein 1B), encodes components of the BAF chromatin remodeling complexes. Here, we report a case of a 3-year 8-month-old male with a novel nonsense variant (NM_001374820.1:c.4282C > T, p.(Gln1428*)) in the ARID1B gene, which was identified with whole-exome sequencing. He showed clinical symptoms of cleft soft palate, distinctive facial features (flat nasal bridge, thick eyebrows, and long eyelashes), right cryptorchidism, and hypertrichosis that partially overlapped with CSS. One of the most characteristic features of CSS is absent/hypoplastic fifth distal phalanx. He showed no obvious clinical finding in the lengths of his fingers or in the formation of his fingernails. However, radiographic analyses of the metacarpophalangeal bones revealed shortening of all the distal phalanges and fifth middle phalanges, suggesting brachydactyly. We performed mRNA analyses and revealed that both nonsense-mediated decay and nonsense-associated altered splicing were simultaneously caused by the c.4282C > T nonsense variant. The proband's clinical manifestations fit the previously reported criteria of disease for CSS or intellectual disability with ARID1B variant. Altogether, we suggest that c.4282C > T is a pathogenic variant that causes this clinical phenotype.

Compound heterozygous variants of the NARS2 gene in siblings with developmental delay, epilepsy, and neonatal diabetes syndrome.

Neonatal diabetes mellitus (NDM) with developmental delay and epilepsy is classified as developmental delay, epilepsy, and neonatal diabetes (DEND) syndrome. The majority of DEND syndrome are due to severely damaging variants of K-ATP channels, and few mitochondria-related genes have been reported. We report here two Japanese siblings who were clinically diagnosed with DEND syndrome in whom NARS2 compound heterozygous variants were detected. Patient 1 was a 3-year-old girl and presented with diabetes ketoacidosis at 3 months old. Patient 2 was a 1-year-old boy who presented with severe hyperglycemia and started insulin therapy at 3 days old. After the first episodes, they both presented with severe developmental delay, hearing loss and treatment-resistant epilepsy accompanied by progressive brain atrophy. Whole-exome sequencing revealed compound heterozygous NARS2 p.R159C and p.L217V variants, and the GATA4 p.P407Q variant in both patients. They were treated by mitochondrial supportive therapy of vitamin B1, L-carnitine, and coenzyme Q10. Patient 2 was withdrawn from insulin therapy at 6 months old. This is the first report of NDM in which variants of the NARS2 gene coding mitochondrial protein were detected. Genetic analysis including mitochondrial genes should be considered in patients with neonatal onset diabetes associated with neurogenic symptoms.

A Mild Clinical Phenotype with Myopathic and Hemolytic Forms of Phosphoglycerate Kinase Deficiency (PGK Osaka): A Case Report and Literature Review.

Phosphoglycerate kinase (PGK) deficiency is an X-linked disorder characterized by a combination of hemolytic anemia, myopathy, and brain involvement. We herein report a Japanese man who had several episodes of rhabdomyolysis but was training strenuously to be a professional boxer. Mild hemolytic anemia was noted. The enzymatic activity of PGK was significantly reduced, and a novel missense mutation, p.S62N, was identified in the PGK1 gene. A literature review revealed only one case with a mixed hemolytic and myopathic phenotype like ours. This mild phenotype indicates the complex pathophysiology of PGK deficiency and suggests the benefits of dietary control and exercise.