An unexpected presentation of very severe hypertriglyceridemia in a boy with Coffin-Lowry syndrome: a case report.

BACKGROUND: Coffin-Lowry syndrome (CLS) is a rare X-linked condition with intellectual disability, growth retardation, characteristic facies and skeletal anomalies. To date, hypertriglyceridemia has not been reported in literature to be associated with CLS. CASE PRESENTATION: Herein, we report a case of very severe hypertriglyceridemia 32 mmol/L (2834 mg/dL) detected incidentally at three months old in an otherwise well boy born late preterm with intrauterine growth restriction, when he presented with lipaemic plasma. He was later diagnosed with CLS. No pathogenic mutations were found for hypertriglyceridemia, and no secondary causes could explain his very severe hypertriglyceridemia. CONCLUSIONS: The very severe hypertriglyceridemia in this case may appear to be a serious presentation of an unrecognised clinical feature of CLS, further expanding its phenotype.

Delayed postnatal brain development and ontogenesis of behavior and cognition in a mouse model of intellectual disability.

Intellectual disability (ID) is a neurodevelopmental disorder associated with impaired cognitive and adaptive behaviors and represents a major medical issue. Although ID-patients develop behavioral problems and are diagnosed during childhood, most behavioral studies in rodent models have been conducted in adulthood, missing precocious phenotypes expressed during this critical time-window characterized by intense brain plasticity. Here, we selectively assessed postnatal ontogenesis of behavioral and cognitive processes, as well as postnatal brain development in the male Rsk2-knockout mouse model of the Coffin-Lowry syndrome, an X-linked disorder characterized by ID and neurological abnormalities. While Rsk2-knockout mice were born healthy, a longitudinal MRI study revealed a transient secondary microcephaly and a persistent reduction of hippocampal and cerebellar volumes. Specific behavioral parameters from postnatal day 4 (P4) unveiled delayed acquisition of sensory-motor functions and alterations of spontaneous and cognitive behaviors during adolescence, which together, represent hallmarks of neurodevelopmental disorders. Together, our results suggest for the first time that RSK2, an effector of the MAPK signaling pathways, plays a crucial role in brain and cognitive postnatal development. This study also provides new relevant measures to characterize postnatal cognitive development of mouse models of ID and to design early therapeutic approaches.

Exploring the impacts of a coffin-lying experience on life and death attitudes of medical and nursing students: preliminary findings.

BACKGROUND: Physicians and nurses often exhibit strong negative emotional and behavioral reactions when patients they care for die, and death education helps them cope with these difficulties. When implementing death education, the literature shows that experiential activities are more effective than lecturing, and progressive exposure is the best way to reduce death anxieties. This study examined the effects of coffin-lying, an activity sometimes seen in Asian cultures, on life and death attitudes of medical and nursing students. METHODS: During a period from 2020 to 2021, 134 medical and nursing students from a medical university in northern Taiwan voluntarily participated in this study. Among them, 53 were in the experimental group, who participated in a coffin-lying activity for nearly 3 hours, and the other 81 were in the control group. All participants filled out questionnaires 1 week before the activity (T1), 1 week after the activity (T2), and 6 ~ 11 weeks after the activity (T3). Three waves of data were analyzed by a repeated-measure multivariate analysis of variance (MANOVA). RESULTS: The effects of "love and care" and "feeling of existence" were only manifested at T2, however, the scores of "fear of death" and "death avoidance" between the experimental and control groups significantly differed at T2 and T3. In addition, there were no significant differences between the experimental and control groups in "neutral acceptance", "approach acceptance", or "escape acceptance". CONCLUSIONS: The coffin-lying activity based on desensitization was effective in improving "fear of death" and "death avoidance", and the effects were sustained to 6 ~ 11 weeks. Coffin-lying is not only a well-designed activity that quickly reduces negative tendencies toward death, but it is also worth adopting by medical and nursing schools to make death education more comprehensive.

Defective synaptic plasticity in a model of Coffin-Lowry syndrome is rescued by simultaneously targeting PKA and MAPK pathways.

Empirical and computational methods were combined to examine whether individual or dual-drug treatments can restore the deficit in long-term synaptic facilitation (LTF) of the Aplysia sensorimotor synapse observed in a cellular model of Coffin-Lowry syndrome (CLS). The model was produced by pharmacological inhibition of p90 ribosomal S6 kinase (RSK) activity. In this model, coapplication of an activator of the mitogen-activated protein kinase (MAPK) isoform ERK and an activator of protein kinase A (PKA) resulted in enhanced phosphorylation of RSK and enhanced LTF to a greater extent than either drug alone and also greater than their additive effects, which is termed synergism. The extent of synergism appeared to depend on another MAPK isoform, p38 MAPK. Inhibition of p38 MAPK facilitated serotonin (5-HT)-induced RSK phosphorylation, indicating that p38 MAPK inhibits activation of RSK. Inhibition of p38 MAPK combined with activation of PKA synergistically activated both ERK and RSK. Our results suggest that cellular models of disorders that affect synaptic plasticity and learning, such as CLS, may constitute a useful strategy to identify candidate drug combinations, and that combining computational models with empirical tests of model predictions can help explain synergism of drug combinations.

Mitral valve repair and tricuspid annuloplasty for Coffin-Lowry syndrome.

Coffin-Lowry syndrome is a rare X-linked disorder that shows a varied clinical presentation. We report cardiac involvement, particularly abnormalities of mitral valve morphology, in a 14-year-old male adolescent with a known diagnosis of Coffin-Lowry syndrome, who presented with easy fatigability. Echocardiography revealed severe mitral and moderate tricuspid regurgitation, and the papillary muscles were attached to the base of the left ventricle. We performed tricuspid annuloplasty and mitral valve repair using two artificial chordae and a semi-rigid full ring. The patient's postoperative course was uneventful. Postoperative echocardiography revealed reduced mitral regurgitation, and his cardiac failure improved.

Novel RPS6KA3 mutations cause Coffin-Lowry syndrome in two patients and concurrent compulsive eyebrow-pulling behavior in one of them.

Coffin-Lowry syndrome (CLS) is a rare X-linked disorder that, usually affects males, presenting with intellectual disability, short stature, growth retardation, short hands, hyperextensible fingers and progressive kyphoscoliosis. Due to skewed X chromosome inactivation, the clinical presentations of the affected females vary greatly and clinical manifestations could range from mild intellectual disability to typical features of CLS in males. Here, we reported two different novel RPS6KA3 gene mutations in two unrelated CLS patients and also described concomitant compulsive eyebrow-pulling behavior in one of these cases for the first time in the literature.

Coffin-Lowry Syndrome Induced by RPS6KA3 Gene Variation in China: A Case Report in Twins.

Background and objectives: Coffin-Lowry Syndrome (CLS), a rare neurodegenerative disorder, is mainly diagnosed based on clinical manifestations and molecular analyses. In total, about 20 cases of CLS have been reported in China. Here, we report two cases of CLS in identical twin brothers and examine their potential causative mutations. Methods: The Trio mode was used in this analysis, i.e., DNA from the proband and his parents was sequenced. Furthermore, DNA from the proband's twin brother was used for confirmation. Results: A hemizygous variation was detected in the 11th exon of the RPS6KA3 gene, c.898C>T (p.R300*) of the proband, and the same site variation was detected in his identical twin brother; however, the mutation was not detected in his parents. Conclusions: The RPS6KA3 gene mutation c.898C>T (p.R300*) is the causative factor of familial CLS. The variant detected was reported for the first time in the Chinese population. Additionally, by analyzing the previous literature, we were able to summarize the phenotypic and genetic characteristics of GLS in China.

Short Bones, Renal Stones, and Diagnostic Moans: Hypercalcemia in a Girl Found to Have Coffin-Lowry Syndrome.

Pathogenic variants in RPS6KA3 are associated with Coffin-Lowry syndrome (CLS), an X-linked semidominant disorder characterized by intellectual disability, stimulus-induced drop attacks, distinctive facial features, progressive kyphoscoliosis, and digit anomalies in hemizygous males. Heterozygous females may also have features of CLS; however, there can be considerable phenotypic variation, often attributed to ratios of X-inactivation in various tissue types. Although skeletal anomalies and short stature are hallmarks of CLS, hypercalcemia has not been reported. Here we describe a 30-month-old girl with gross motor delays, short stature, dysmorphic features, bilateral duplicated renal collecting systems, and no family history of hypercalcemia who required multiple admissions for idiopathic hypercalcemia necessitating bisphosphonate infusions at 12.5 and 15 months of age. A maternally inherited likely-pathogenic variant in RPS6KA3 was identified by trio exome sequencing, consistent with the diagnosis of CLS in the proband and her mother. Maternal history was notable only for decreased height compared to first-degree relatives, bilateral genu valgum, and a bicornuate uterus; she was later found to also have a partially duplicated left renal collecting system. Subsequent X-inactivation studies in blood aligned with the phenotypic variation between mother and daughter. Although hypercalcemia is not a reported feature in CLS, there is evidence of interrupted osteoblast differentiation, providing a potential mechanism for hypercalcemia in this genetic condition. The hypercalcemia in this case may represent a severe presentation of an unrecognized clinical feature in CLS that resolves with age. This case further highlights the intrafamilial phenotypic variation of CLS among females, suggesting X-inactivation as the underlying mechanism, and demonstrates the value of exome sequencing in patients for whom a genetic disorder is highly suspected but not identified despite thorough evaluation.

Accelerated tooth movement in Rsk2-deficient mice with impaired cementum formation.

Coffin-Lowry-Syndrome (CLS) is a X-linked mental retardation characterized by skeletal dysplasia and premature tooth loss. We and others have previously demonstrated that the ribosomal S6 kinase RSK2, mutated in CLS, is essential for bone and cementum formation; however, it remains to be established whether RSK2 plays also a role in mechanically induced bone remodeling during orthodontic tooth movement (OTM). We, therefore, performed OTM in wild-type (WT) mice and Rsk2-deficient mice using Nitinol tension springs that were fixed between the upper left molars and the incisors. The untreated contralateral molars served as internal controls. After 12 days of OTM, the jaws were removed and examined by micro-computed tomography (µCT), decalcified histology, and immunohistochemistry. Our analysis of the untreated teeth confirmed that the periodontal phenotype of Rsk2-deficient mice is characterized by alveolar bone loss and hypoplasia of root cementum. Quantification of OTM using µCT revealed that OTM was more than two-fold faster in Rsk2-deficient mice as compared to WT. We also observed that OTM caused alveolar bone loss and root resorptions in WT and Rsk2-deficient mice. However, quantification of these orthodontic side effects revealed no differences between WT and Rsk2-deficient mice. Taken together, Rsk2 loss-of-function accelerates OTM in mice without causing more side effects.

Customised next-generation sequencing multigene panel to screen a large cohort of individuals with chromatin-related disorder.

BACKGROUND: The regulation of the chromatin state by epigenetic mechanisms plays a central role in gene expression, cell function, and maintenance of cell identity. Hereditary disorders of chromatin regulation are a group of conditions caused by abnormalities of the various components of the epigenetic machinery, namely writers, erasers, readers, and chromatin remodelers. Although neurological dysfunction is almost ubiquitous in these disorders, the constellation of additional features characterizing many of these genes and the emerging clinical overlap among them indicate the existence of a community of syndromes. The introduction of high-throughput next generation sequencing (NGS) methods for testing multiple genes simultaneously is a logical step for the implementation of diagnostics of these disorders. METHODS: We screened a heterogeneous cohort of 263 index patients by an NGS-targeted panel, containing 68 genes associated with more than 40 OMIM entries affecting chromatin function. RESULTS: This strategy allowed us to identify clinically relevant variants in 87 patients (32%), including 30 for which an alternative clinical diagnosis was proposed after sequencing analysis and clinical re-evaluation. CONCLUSION: Our findings indicate that this approach is effective not only in disorders with locus heterogeneity, but also in order to anticipate unexpected misdiagnoses due to clinical overlap among cognate disorders. Finally, this work highlights the utility of a prompt diagnosis in such a clinically and genetically heterogeneous group of disorders that we propose to group under the umbrella term of chromatinopathies.

A new missense mutation in DPF2 gene related to Coffin Siris syndrome 7: Description of a mild phenotype expanding DPF2-related clinical spectrum and differential diagnosis among similar syndromes epigenetically determined.

BACKGROUND: Coffin-Siris syndrome (CSS) is a neurodevelopmental disorder characterized by somatic dysmorphic features, developmental and speech delay. It is due to mutations in many different genes, belonging to BAF chromatin-remodelling complex. The last gene involved in this complex, recently individuated and related to CSS, was DPF2, although only nine patients have been reported until now. METHOD: Here we report on a boy with a history of developmental delay, especially regarding speech and language, and dysmorphic features resembling a syndromic condition. Array-Comparative Genomic Hybridization (CGH) and a custom Next Generation Sequencing (NGS) panel including developmental delay related genes were executed. RESULTS: Array-CGH was negative while NGS panel revealed a novel mutation in DPF2 gene. CONCLUSIONS: We add the clinical description of another patient with a novel mutation in DPF2, with a mild phenotype, thus trying to contribute to enlarge CSS phenotypic variability. Moreover, we briefly discuss about cohesinopathies and major differential diagnosis among syndromes with phenotypes overlapping to CSS.

Accelerated tooth movement in Rsk2-deficient mice with impaired cementum formation / 国际口腔科学杂志·英文版

Coffin-Lowry-Syndrome (CLS) is a X-linked mental retardation characterized by skeletal dysplasia and premature tooth loss. We and others have previously demonstrated that the ribosomal S6 kinase RSK2, mutated in CLS, is essential for bone and cementum formation; however, it remains to be established whether RSK2 plays also a role in mechanically induced bone remodeling during orthodontic tooth movement (OTM). We, therefore, performed OTM in wild-type (WT) mice and Rsk2-deficient mice using Nitinol tension springs that were fixed between the upper left molars and the incisors. The untreated contralateral molars served as internal controls. After 12 days of OTM, the jaws were removed and examined by micro-computed tomography (µCT), decalcified histology, and immunohistochemistry. Our analysis of the untreated teeth confirmed that the periodontal phenotype of Rsk2-deficient mice is characterized by alveolar bone loss and hypoplasia of root cementum. Quantification of OTM using µCT revealed that OTM was more than two-fold faster in Rsk2-deficient mice as compared to WT. We also observed that OTM caused alveolar bone loss and root resorptions in WT and Rsk2-deficient mice. However, quantification of these orthodontic side effects revealed no differences between WT and Rsk2-deficient mice. Taken together, Rsk2 loss-of-function accelerates OTM in mice without causing more side effects.

BRM: the core ATPase subunit of SWI/SNF chromatin-remodelling complex-a tumour suppressor or tumour-promoting factor?

BRM (BRAHMA) is a core, SWI2/SNF2-type ATPase subunit of SWI/SNF chromatin-remodelling complex (CRC) involved in various important regulatory processes including development. Mutations in SMARCA2, a BRM-encoding gene as well as overexpression or epigenetic silencing were found in various human diseases including cancer. Missense mutations in SMARCA2 gene were recently connected with occurrence of Nicolaides-Baraitser genetics syndrome. By contrast, SMARCA2 duplication rather than mutations is characteristic for Coffin-Siris syndrome. It is believed that BRM usually acts as a tumour suppressor or a tumour susceptibility gene. However, other studies provided evidence that BRM function may differ depending on the cancer type and the disease stage, where BRM may play a role in the disease progression. The existence of alternative splicing forms of SMARCA2 gene, leading to appearance of truncated functional, loss of function or gain-of-function forms of BRM protein suggest a far more complicated mode of BRM-containing SWI/SNF CRCs actions. Therefore, the summary of recent knowledge regarding BRM alteration in various types of cancer and highlighting of differences and commonalities between BRM and BRG1, another SWI2/SNF2 type ATPase, will lead to better understanding of SWI/SNF CRCs function in cancer development/progression. BRM has been recently proposed as an attractive target for various anticancer therapies including the use of small molecule inhibitors, synthetic lethality induction or proteolysis-targeting chimera (PROTAC). However, such attempts have some limitations and may lead to severe side effects given the homology of BRM ATPase domain to other ATPases, as well as due to the tissue-specific appearance of BRM- and BRG1-containing SWI/SNF CRC classes. Thus, a better insight into BRM-containing SWI/SNF CRCs function in human tissues and cancers is clearly required to provide a solid basis for establishment of new safe anticancer therapies.

An unusual cause for Coffin-Lowry syndrome: Three brothers with a novel microduplication in RPS6KA3.

Coffin-Lowry syndrome (CLS) is a rare X-linked disorder characterized by moderate to severe intellectual disability, hypotonia, craniofacial features, tapering digits, short stature, and skeletal deformities. Using whole exome sequencing and high-resolution targeted comparative genomic hybridization array analysis, we identified a novel microduplication encompassing exons five through nine of RPS6KA3 in three full brothers. Each brother presented with intellectual disability and clinical and radiographic features consistent with CLS. qRT-PCR analyses performed on mRNA from the peripheral blood of the three siblings revealed a marked reduction of RPS6KA3 levels suggesting a loss-of-function mechanism. PCR analysis of the patients' cDNA detected a band greater than expected for an exon 4-10 amplicon, suggesting this was likely a direct duplication that lies between exons 4 through 10, which was later confirmed by Sanger sequencing. This microduplication is only the third intragenic duplication of RPS6KA3, and the second and smallest reported to date thought to cause CLS. Our study further supports the clinical utility of methods such as next-generation sequencing and high-resolution genomic arrays to detect small intragenic duplications. These methods, coupled with expression studies and cDNA structural analysis have the capacity to confirm the diagnosis of CLS in these rare cases.

Coffin-Lowry syndrome in Chinese.

Coffin-Lowry syndrome (CLS) is a well-described syndrome characterized by intellectual disability, growth retardation, recognizable dysmorphic features, and skeletal changes. It is an X-linked syndrome where males are more severely affected and females have high variability in clinical presentations. This case series reports nine molecularly confirmed Chinese CLS patients from six unrelated families (three with familial variants and three with de novo variants). There is a wide genotypic spectrum with five novel variants in RPS6KA3 gene. Clinical phenotype and facial features of these Chinese CLS patients are comparable to what has been described in other ethnicities.

[Analysis of RPS6KA3 gene mutation in a Chinese pedigree affected with Coffin-Lowry syndrome].

OBJECTIVE: To identify potential mutations of the CLS gene in a Chinese pedigree affected with Coffin-Lowry syndrome. METHODS: Whole exome sequencing was applied to detect potential mutation in the proband, and the result was verified by Sanger sequencing. RESULTS: The proband was found to carry a c.966_967delAA (p.Arg323Thr fs*11) deletional mutation in the RPS6KA3 gene. The same mutation was also found in his mother. CONCLUSION: The c.966_967delAA (p.Arg323Thr fs*11) deletional mutation of the RPS6KA3 gene probably underlies the disorder in this pedigree.

Severe Restrictive Lung Disease in One of the Oldest Documented Males With Coffin-Lowry Syndrome.

Coffin-Lowry syndrome is expressed as different phenotypes in males and females. In males, it is characterized by facial abnormalities, marked developmental disability, and skeletal changes. Approximately 80% of cases are associated with kyphoscoliosis, which can be quite severe, as seen in our patient, causing paraplegia and restrictive lung disease. In this article, we present the third oldest documented male case of Coffin-Lowry syndrome with severe kyphoscoliosis, paraplegia, and restrictive lung disease.

De Novo SOX4 Variants Cause a Neurodevelopmental Disease Associated with Mild Dysmorphism.

SOX4, together with SOX11 and SOX12, forms group C of SRY-related (SOX) transcription factors. They play key roles, often in redundancy, in multiple developmental pathways, including neurogenesis and skeletogenesis. De novo SOX11 heterozygous mutations have been shown to cause intellectual disability, growth deficiency, and dysmorphic features compatible with mild Coffin-Siris syndrome. Using trio-based exome sequencing, we here identify de novo SOX4 heterozygous missense variants in four children who share developmental delay, intellectual disability, and mild facial and digital morphological abnormalities. SOX4 is highly expressed in areas of active neurogenesis in human fetuses, and sox4 knockdown in Xenopus embryos diminishes brain and whole-body size. The SOX4 variants cluster in the highly conserved, SOX family-specific HMG domain, but each alters a different residue. In silico tools predict that each variant affects a distinct structural feature of this DNA-binding domain, and functional assays demonstrate that these SOX4 proteins carrying these variants are unable to bind DNA in vitro and transactivate SOX reporter genes in cultured cells. These variants are not found in the gnomAD database of individuals with presumably normal development, but 12 other SOX4 HMG-domain missense variants are recorded and all demonstrate partial to full activity in the reporter assay. Taken together, these findings point to specific SOX4 HMG-domain missense variants as the cause of a characteristic human neurodevelopmental disorder associated with mild facial and digital dysmorphism.

Analysis of RPS6KA3 gene mutation in a Chinese pedigree affected with Coffin-Lowry syndrome / 中华医学遗传学杂志

OBJECTIVE@#To identify potential mutations of the CLS gene in a Chinese pedigree affected with Coffin-Lowry syndrome.@*METHODS@#Whole exome sequencing was applied to detect potential mutation in the proband, and the result was verified by Sanger sequencing.@*RESULTS@#The proband was found to carry a c.966_967delAA (p.Arg323Thr fs*11) deletional mutation in the RPS6KA3 gene. The same mutation was also found in his mother.@*CONCLUSION@#The c.966_967delAA (p.Arg323Thr fs*11) deletional mutation of the RPS6KA3 gene probably underlies the disorder in this pedigree.