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BMC Medical Genomics Jun 2024TTN is a complex gene with large genomic size and highly repetitive structure. Pathogenic variants in TTN have been reported to cause a range of skeletal muscle and...
BACKGROUND
TTN is a complex gene with large genomic size and highly repetitive structure. Pathogenic variants in TTN have been reported to cause a range of skeletal muscle and cardiac disorders. Homozygous or compound heterozygous mutations tend to cause a wide spectrum of phenotypes with congenital or childhood onset. The onset and severity of the features were considered to be correlated with the types and location of the TTN variants.
METHODS
Whole-exome sequencing was performed on three unrelated families presenting with fetal akinesia deformation sequence (FADS), mainly characterized by reduced fetal movements and limb contractures. Sanger sequencing was performed to confirm the variants. RT-PCR analysis was performed.
RESULTS
TTN c.38,876-2 A > C, a meta transcript-only variant, with a second pathogenic or likely pathogenic variant in trans, was observed in five affected fetuses from the three families. Sanger sequencing showed that all the fetal variants were inherited from the parents. RT-PCR analysis showed two kinds of abnormal splicing, including intron 199 extension and skipping of 8 bases.
CONCLUSIONS
Here we report on three unrelated families presenting with FADS caused by four TTN variants. In addition, our study demonstrates that pathogenic meta transcript-only TTN variant can lead to defects which is recognizable prenatally in a recessive manner.
Topics: Humans; Female; Connectin; Pedigree; Male; Exome Sequencing; Arthrogryposis; Contracture; Mutation; Pregnancy; Fetus; Adult
PubMed: 38937733
DOI: 10.1186/s12920-024-01946-z -
Acta Ortopedica Brasileira 2024To evaluate patients with arthrogryposis submitted to extensive surgical treatment with a minimum of 10 years of follow-up regarding the clinical and radiological...
OBJECTIVE
To evaluate patients with arthrogryposis submitted to extensive surgical treatment with a minimum of 10 years of follow-up regarding the clinical and radiological aspects and the quality of life, using the 36-Item Short Form (SF-36) and the Disease-Specific Instrument (DSI).
METHODS
A retrospective study selected 33 patients, totaling 64 operated feet.
RESULTS
The mean age of the patients was 17.9 years (12-39 years), and the mean follow-up time was 14.8 years (11-17). Amyoplasia represented 78.7% of syndromic diagnoses. Isolated posteromedial lateral release (PMLR) was performed in 21.8% of the feet, 27.2% of which required additional bone surgery, and about 50 feet (78.1%) were submitted to PMLR, lateral column shortening, and/or talectomy. In total, 46 talectomies were performed (71.8% of the feet), out of which 44 were the first procedure of choice. SF-36 questionnaire was evaluated and showed that 93.9% of the patients did not have restrictive and disabling pain, and the same percentage considered themselves as healthy and had good expectations for the future.
CONCLUSION
Arthrogrypotic feet are difficult to treat, require many recurrent surgical procedures, and relapses are the rule. Stiffness is a common feature of these feet, and residual deformities were frequent.
PubMed: 38933350
DOI: 10.1590/1413-785220243202e275561 -
Genes May 2024Pathogenic variants in the gene lead to a spectrum of rare autosomal recessive phenotypes, including osteogenesis imperfecta (OI) Type XI, Bruck syndrome Type I (BS I),...
Pathogenic variants in the gene lead to a spectrum of rare autosomal recessive phenotypes, including osteogenesis imperfecta (OI) Type XI, Bruck syndrome Type I (BS I), and the congenital arthrogryposis-like phenotype (AG), each with variable clinical manifestations that are crucial for diagnosis. This study analyzed the clinical-genetic characteristics of patients with these conditions, focusing on both known and newly identified variants. We examined data from 15 patients, presenting symptoms of OI and joint contractures. Diagnostic methods included genealogical analysis, clinical assessments, radiography, whole exome sequencing, and direct automated Sanger sequencing. We diagnosed 15 patients with phenotypes due to biallelic variants-4 with OI Type XI, 10 with BS I, and 1 with the AG-like phenotype-demonstrating polymorphism in disease severity. Ten pathogenic variants were identified, including three novel ones, c.1373C>T (p.Pro458Leu), c.21del (p.Pro7fs), and c.831_832insCG (p.Gly278Argfs), and a recurrent variant, c.831dup (p.Gly278Argfs). Variant c.1490G>A (p.Trp497Ter) was found in two unrelated patients, causing OI XI in one and BS I in the other. Additionally, two unrelated patients with BS I and epidermolysis bullosa shared identical homozygous and variants. This observation illustrates the diversity of -related pathology and the importance of considering the full spectrum of phenotypes in clinical diagnostics.
Topics: Humans; Tacrolimus Binding Proteins; Male; Female; Arthrogryposis; Phenotype; Osteogenesis Imperfecta; Child; Child, Preschool; Pedigree; Exome Sequencing; Adolescent; Mutation; Infant; Adult; Nervous System Malformations
PubMed: 38927610
DOI: 10.3390/genes15060674 -
Brain : a Journal of Neurology Jun 2024Dominant missense mutations of the calcium-permeable cation channel TRPV4 cause Charcot-Marie-Tooth disease (CMT) type 2C and two forms of distal spinal muscular...
Dominant missense mutations of the calcium-permeable cation channel TRPV4 cause Charcot-Marie-Tooth disease (CMT) type 2C and two forms of distal spinal muscular atrophy. These conditions are collectively referred to as TRPV4-related neuromuscular disease and share features of motor greater than sensory dysfunction and frequent vocal fold weakness. Pathogenic variants lead to gain of ion channel function that can be rescued by TRPV4 antagonists in cellular and animal models. As small molecule TRPV4 antagonists have proven safe in trials for other disease indications, channel inhibition is a promising therapeutic strategy for TRPV4 patients. However, the current knowledge of the clinical features and natural history of TRPV4-related neuromuscular disease is insufficient to enable rational clinical trial design. To address these issues, we developed a TRPV4 patient database and administered a TRPV4-specific patient questionnaire. Here, we report demographic and clinical information, including CMT examination scores (CMTES), from 68 patients with known pathogenic TRPV4 variants, 40 of whom also completed the TRPV4 patient questionnaire. TRPV4 patients showed a bimodal age of onset, with the largest peak occurring in the first 2 years of life. Compared to CMT1A patients, TRPV4 patients showed distinct symptoms and signs, manifesting more ambulatory difficulties and more frequent involvement of proximal arm and leg muscles. Although patients reported fewer sensory symptoms, sensory dysfunction was often detected clinically. Many patients were affected by vocal fold weakness (55%) and shortness of breath (55%), and 11% required ventilatory support. Skeletal abnormalities were common, including scoliosis (64%), arthrogryposis (33%), and foot deformities. Strikingly, patients with infantile onset of disease showed less sensory involvement and less progression of symptoms. These results highlight distinctive clinical features in TRPV4 patients, including motor-predominant disease, proximal arm and leg weakness, severe ambulatory difficulties, vocal fold weakness, respiratory dysfunction, and skeletal involvement. In addition, patients with infantile onset of disease appeared to have a distinct phenotype with less apparent disease progression based on CMTES. These collective observations indicate that clinical trial design for TRPV4-related neuromuscular disease should include outcome measures that reliably capture non-length dependent motor dysfunction, vocal fold weakness, and respiratory disease.
PubMed: 38917025
DOI: 10.1093/brain/awae201 -
Gene Jun 2024Mutated skeletal muscle ryanodine receptor-1 (RYR1) gene is associated with a spectrum of autosomal dominant and recessive RyR1-related disorders with a wide phenotype....
Mutated skeletal muscle ryanodine receptor-1 (RYR1) gene is associated with a spectrum of autosomal dominant and recessive RyR1-related disorders with a wide phenotype. This report describes a variable phenotype associated with a previously unreported RYR1 frameshift pathogenic variant, (NM_000540.2) c.12815_12825del; p.Ala4272Glyfs*307, common in Libyan Jews. Clinical and genetic features of 14 carriers from 8 unrelated families were collected. There were 12 heterozygotes and 2 compound heterozygotes. Six heterozygotes (median age 49.8) were asymptomatic, and six (median age 24.5) presented with myopathy (n = 3) or severe arthrogryposis-like features, severe scoliosis, pes planus, post-anesthesia malignant hyperthermia, or cystic hygroma (in a fetus) (n = 1 each). None had an abnormal echocardiogram study or elevated creatine phosphokinase (CPK) levels. One bi-allelic carrier had a severe skeletal phenotype and myopathy; the other was a fetus with a cystic hygroma. Assessment of variant frequency in 447 Libyan Jews who underwent exome testing for unrelated reason yielded a prevalence of 1:55. The RYR1 p.Ala4272Glyfs*307 variant is common in Libyan Jews. It is associated with a broad phenotypic spectrum, with possible presentation among heterozygotes. Further genotype-phenotype studies are essential to delineate the clinical significance of the variant in mono- and bi-allelic carriers.
PubMed: 38914246
DOI: 10.1016/j.gene.2024.148725 -
Cureus May 2024Arthrogryposis multiplex congenita (AMC) is a rare condition characterized by multiple joint contractures at birth, affecting two or more body areas. The clinical...
Arthrogryposis multiplex congenita (AMC) is a rare condition characterized by multiple joint contractures at birth, affecting two or more body areas. The clinical examination revealed physical abnormalities indicative of AMC, including joint contractures, clubfeet, and scoliosis. The diagnostic evaluation confirmed the clinical suspicion, and prompt management was initiated to address respiratory distress and potential sepsis. Early diagnosis and multidisciplinary care are essential for optimizing outcomes in neonates with AMC. We present the case of a one-day-old neonate who exhibited immediate respiratory distress upon birth and was born via a lower segment cesarean section (LSCS) to a 31-year-old mother. This case underscores the importance of recognizing prenatal ultrasound findings suggestive of AMC and implementing appropriate postnatal care strategies for affected neonates. Early diagnosis and multidisciplinary care are essential for optimizing outcomes in neonates with AMC.
PubMed: 38903284
DOI: 10.7759/cureus.60729 -
Veterinary Research Communications Jun 2024Two 1-day-old full-term female calves from different farms located in the Brazilian state of Rio Grande do Sul were unable to stand due to paresis of the pelvic limbs....
Two 1-day-old full-term female calves from different farms located in the Brazilian state of Rio Grande do Sul were unable to stand due to paresis of the pelvic limbs. Both calves had spina bifida on the spinal lumbar segment and were submitted to euthanasia due to poor prognosis. Postmortem examination revealed cerebellar herniation, caudal displacement of the brainstem, rostral deviation of the cranial nerves, caudal extension of occipital lobes, absence of dorsal lamina of lumbar vertebrae with exposed spinal cord, myelodysplasia, kyphosis, segmental spinal agenesis, renal fusion, muscular atrophy, and arthrogryposis. Histology highlighted myelodysplasia (syringomyelia and diplomyelia) and muscular atrophy. The reverse transcription-polymerase chain reactions for ruminant pestivirus were negative. Based on these lesions, the diagnosis of complex neural tube and skeletal malformations was made. A review of previous publications on calves diagnosed with these malformations, originally called Chiari or Arnold-Chiari malformations, revealed a wide range of nervous system and skeletal lesions. These variations amplified the uncertainty regarding whether all cases represent the same disorder and reinforced the importance of reconfiguring the terminology.
PubMed: 38884867
DOI: 10.1007/s11259-024-10437-6 -
Pediatric Dermatology Jun 2024Musculocontractural Ehlers-Danlos syndrome (MC-EDS) is a rare entity worldwide with underlying pathogenic variant in the carbohydrate sulfotransferase 14 (CHST14) gene....
Musculocontractural Ehlers-Danlos syndrome (MC-EDS) is a rare entity worldwide with underlying pathogenic variant in the carbohydrate sulfotransferase 14 (CHST14) gene. Previous reports of the same entity from India were of two unrelated cases. Ours is the first report of two siblings in an Indian family with craniofacial dysmorphism and distal arthrogryposis with a clinical diagnosis of EDS, where an underlying pathogenic variant in CHST14 was detected by exome sequencing.
PubMed: 38881098
DOI: 10.1111/pde.15653 -
Orphanet Journal of Rare Diseases Jun 2024Arthrogryposis multiplex congenita (AMC) is a group of rare musculoskeletal conditions that is associated with complex healthcare needs and long-term follow up. The...
BACKGROUND
Arthrogryposis multiplex congenita (AMC) is a group of rare musculoskeletal conditions that is associated with complex healthcare needs and long-term follow up. The literature reports significant direct, indirect, and psychosocial costs for caregivers of children with neuromuscular conditions. Due to mobility limitations and frequent hospital visits, caring for a child with AMC is complex. Other challenges experienced by caregivers include financial strain, job changes, changes in interpersonal relationships and abandonment. This study was aimed at exploring the lived experience of caregivers of children with AMC.
METHODS
The present study is part of a larger global mixed methods study. In the initial quantitative aspect of the study, caregivers (n = 158) of children and youths with AMC (aged 0-21 years) responded to a cost of care survey on an electronic platform. Of the 158 participants, 13 caregivers then further consented to participate in the qualitative aspect of the study in which a 60-min semi-structured, individual interview was conducted remotely. Open-ended questions were developed to gain a deeper understanding of the direct and indirect costs of care, their impact on the caregivers' lives and the quality of the care-giving experience. Interviews were transcribed, and a coding scheme was developed drawing from both the existing literature and the content of the interviews. A deductive and inductive thematic analysis was used to analyze the qualitative data using the NVivo® qualitative data analysis software.
RESULTS AND CONCLUSION
Five themes describing the experiences of caregivers of children with AMC emerged from the analysis of the qualitative data: 1. Impact of the caregiving experience; 2. Cost of childcare; 3. Support system for care; 4. Managing and navigating care; 5. Supporting the child's growth and development. In addition to the results of the thematic analysis, specific recommendations shared by the caregivers included the need for support groups and provision of support to youths to prepare them for adolescence. These findings will inform resource allocation, policymaking, and support services for children with rare conditions, their caregivers and families.
Topics: Humans; Arthrogryposis; Caregivers; Child; Adolescent; Female; Male; Child, Preschool; Infant; Young Adult; Adult; Rare Diseases; Qualitative Research; Infant, Newborn; Musculoskeletal Diseases
PubMed: 38877508
DOI: 10.1186/s13023-024-03224-8 -
Neurology Jul 2024
Topics: Humans; Arthrogryposis; Female; Pregnancy; Myasthenic Syndromes, Congenital; Adult; Abnormalities, Multiple; Malignant Hyperthermia; Skin Abnormalities
PubMed: 38870465
DOI: 10.1212/WNL.0000000000209602