COL12A1 Gene Variant and a Review of the Literature: A Case Report of Ullrich Congenital Muscular Dystrophy.

Introduction: Mutations in collagen type IV-associated genes lead to Ullrich congenital muscular dystrophy (UCMD) and Bethlem myopathy (BM). COL12A1 gene mutations have rarely been reported in patients with UCMD- and BM-like disorders not involving COL6 mutations. UCMD-2 results from homozygous mutations in the COL12A1 gene on the long arm of chromosome 6. Pathogenic variants in COL12A1 result in a rare congenital connective tissue/myopathy overlap syndrome under the heading of myopathic Ehlers-Danlos syndrome. COL12A1 dominant pathogenic variants have been rarely reported, and the phenotypic spectrum has not yet been identified. Case Presentation: We describe a female patient aged 2 years and 10 months exhibiting a milder phenotype who presented due to pronounced joint hyperlaxity, frequent falls, and skin lesions. Genetic analysis revealed a homozygous c.8903C>T (p.Pro2968Leu) missense variant that had previously been described but concerning which there had been no clinical report, in the COL12A1 gene. Discussion/Conclusion: This report is presented in order to raise awareness of rare mutations in the COL12A1 gene that affect muscle and connective tissue and to add to the literature in defining the phenotypic spectrum.

Investigation of genotype-phenotype and familial features of Turkish dystrophinopathy patients.

Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) are X-linked recessive allelic muscle diseases caused by dystrophin gene mutations. Eight hundred thirty-seven patients admitted between 1997 and 2022 were included in the study. Two hundred twenty patients were analyzed by multiplex PCR (mPCR) alone. Five hundred ninety-five patients were investigated by multiplex ligation-dependent probe amplification (MLPA), and 54 patients were examined by sequencing. Deletion was detected in 60% (132/220) of the cases in the mPCR group only and in 58.3% (347/595) of the cases with MLPA analysis. The rates of deletion and duplication were 87.7% and 12.3%, respectively, in the MLPA analysis. Single exon deletions were the most common mutation type. The introns 43-55 (81.8%) and exons 2-21 (13.1%) regions were detected as hot spots in deletions. It was determined that 89% of the mutations were suitable for exon skipping therapy. The reading frame rule did not hold in 7.6% of D/BMD cases (17/224). We detected twenty-five pathogenic/likely pathogenic variants in sequencing, five of which were novel variants. Nonsense mutation was the most common small mutation (44%). 21% of DMD patients were familial. We detected germline mosaicism in four families (4.3%) in the large rearrangement group and one gonosomal mosaicism in a family with a nonsense mutation. This is the largest study examining genotype and phenotype data in Turkish D/BMD families investigated by MLPA analysis. The reading frame hypothesis is not valid in all cases. Sharing the genotype and phenotype characteristics of these cases in the literature will shed light on the molecular structure of DMD and guide gene therapy research. In genetic counseling, carrier screening in the family and possible gonadal mosaicism should be emphasized.

Evaluation of the Patients with the Diagnosis of Pontocerebellar Hypoplasia: A Multicenter National Study.

Pontocerebellar hypoplasia (PCH) is a heterogeneous group of neurodegenerative disorders characterized by hypoplasia and degeneration of the cerebellum and pons. We aimed to identify the clinical, laboratory, and imaging findings of the patients with diagnosed PCH with confirmed genetic analysis. We collected available clinical data, laboratory, and imaging findings in our retrospective multicenter national study of 64 patients with PCH in Turkey. The genetic analysis included the whole-exome sequencing (WES), targeted next-generation sequencing (NGS), or single gene analysis. Sixty-four patients with PCH were 28 female (43.8%) and 36 (56.3%) male. The patients revealed homozygous mutation in 89.1%, consanguinity in 79.7%, pregnancy at term in 85.2%, microcephaly in 91.3%, psychomotor retardation in 98.4%, abnormal neurological findings in 100%, seizure in 63.8%, normal biochemistry and metabolic investigations in 92.2%, and dysmorphic findings in 51.2%. The missense mutation was found to be the most common variant type in all patients with PCH. It was detected as CLP1 (n = 17) was the most common PCH related gene. The homozygous missense variant c.419G > A (p.Arg140His) was identified in all patients with CLP1. Moreover, all patients showed the same homozygous missense variant c.919G > T (p.A307S) in TSEN54 group (n = 6). In Turkey, CLP1 was identified as the most common causative gene with the identical variant c.419G > A; p.Arg140His. The current study supports that genotype data on PCH leads to phenotypic variability over a wide phenotypic spectrum.

Feasibility of virtual reality and comparison of its effectiveness to biofeedback in children with Duchenne and Becker muscular dystrophies.

INTRODUCTION/AIMS: The utilization of virtual reality (VR) and biofeedback training, while effective in diverse populations, remains limited in the treatment of Duchenne and Becker muscular dystrophies (D/BMD). This study aimed to determine the feasibility of VR in children with D/BMD and compare the effectiveness of VR and biofeedback in children with D/BMD. METHODS: The study included 25 children with D/BMD. Eight children in the control group participated in a routine follow-up rehabilitation program, while the remaining children were randomly assigned to the VR (n = 9) and biofeedback (n = 8) groups for a 12-week intervention. The following evaluations were performed before, during (week 6), and after treatment: Muscle pain and cramps, laboratory studies, muscle strength, timed performance, function (Motor Function Measurement Scale-32, Vignos, and Brooke Scales), and balance (Pediatric Functional Reach Test and Balance Master System). Motivation for rehabilitation was determined. RESULTS: The median ages were 9.00 (VR), 8.75 (biofeedback), and 7.00 (control) years. The study found no significant differences between groups in pretreatment assessments for most measures, except for tandem step width (p < .05). VR and biofeedback interventions significantly improved various aspects (pain intensity, cramp frequency, cramp severity, muscle strength, timed performance, functional level, and balance) in children with D/BMD (p < .05), while the conventional rehabilitation program maintained patients' current status without any changes. The study found VR and biofeedback equally effective, with VR maintaining children's motivation for rehabilitation longer (p < .05). DISCUSSION: The study showed that both VR and biofeedback appear to be effective for rehabilitation this population, but additional, larger studies are needed.

Alternative splicing expands the clinical spectrum of NDUFS6-related mitochondrial disorders.

PURPOSE: We describe 3 families with Charcot-Marie-Tooth neuropathy (CMT), harboring a homozygous NDUFS6 NM_004553.6:c.309+5G>A variant previously linked to fatal Leigh syndrome. We aimed to characterize clinically and molecularly the newly identified patients and understand the mechanism underlying their milder phenotype. METHODS: The patients underwent extensive clinical examinations. Exome sequencing was done in 4 affected individuals. The functional effect of the c.309+5G>A variant was investigated in patient-derived EBV-transformed lymphoblasts at the complementary DNA, protein, and mitochondrial level. Alternative splicing was evaluated using complementary DNA long-read sequencing. RESULTS: All patients presented with early-onset, slowly progressive axonal CMT, and nystagmus; some exhibited additional central nervous system symptoms. The c.309+5G>A substitution caused the expression of aberrantly spliced transcripts and negligible levels of the canonical transcript. Immunoblotting showed reduced levels of mutant isoforms. No detectable defects in mitochondrial complex stability or bioenergetics were found. CONCLUSION: We expand the clinical spectrum of NDUFS6-related mitochondrial disorders to include axonal CMT, emphasizing the clinical and pathophysiologic overlap between these 2 clinical entities. This work demonstrates the critical role that alternative splicing may play in modulating the severity of a genetic disorder, emphasizing the need for careful consideration when interpreting splice variants and their implications on disease prognosis.

Molecular Diagnosis of Limb-Girdle Muscular Dystrophy Using Next-Generation Sequencing Panels.

Introduction: Limb-girdle muscular dystrophies (LGMDs) are clinically and genetically heterogeneous muscle disorders. We aimed to share the diagnostic yield of an NGS gene panel containing LGMD-related genes and our experience with LGMD. Methods: Between February 2019 and October 2022, patients with a suspicion of LGMD and their relatives were reviewed in terms of demographic, clinical, and individual genetic data, age of symptom onset, sex, clinical features, LGMD types, cardiac involvement, muscle biopsy results, family history, and consanguinity. Our NGS gene panel consisted of ANO5, CAPN3, CAV3, DAG1, DES, DNAJB6, DYSF, FKTN, FLNC, FRKP, GAA, GMPPB, HNRNPDL, ISPD, LIMS2, LMNA, MYOT, PLEC, POMGNT1, POMK, POMT1, POMT2, SGCA, SGCB, SGCD, SGCG, TCAP, TNPO3, TRAPPC11, TRIM32, and TTN genes. Results: The diagnosis rate was 61.1% (11/18). Twelve (80%) patients with LGMD were male and three (20%) were female. The median age was 15.9 (range, 1.5-39) years. Our patient collective was drawn up out of patients with the following variants: LGMDR1 (n = 6; 40%), LGMDR2 (n = 4; 26.6%), LGMDR3 (n = 4; 26.6%), and LGMDR12 (n = 1; 6.7%). Conclusion: The present study showed that the NGS panel has a high success rate in the diagnosis of LGMD and contributes to early diagnosis.

Dual task impact on functional mobility and interaction of functional level and balance in patients with Duchenne muscular dystrophy.

BACKGROUND: Dystrophin, a protein crucial for various brain regions governing higher-order functions like learning and memory is notably absent in individuals with Duchenne muscular dystrophy (DMD). This absence of dystrophin in the brain is believed to underlie cognitive challenges in DMD. Cognitive and motor challenges observed in DMD could potentially hinder the execution of dual tasks. RESEARCH QUESTION: Is there a significant correlation between dual-task performance, functional mobility, and balance in children with DMD? METHOD: The study included 28 participants (14 DMD, 14 typical development). Timed Up and Go (TUG) test results were recorded for single and dual-task conditions (motor-motor, cognitive-motor). Functional level was assessed using Motor Function Measurement-32 (MFM-32), Brooke Upper Extremity Scale, and Vignos Scale. Balance was evaluated using Balance Master System and Pediatric Functional Reach Test (PFRT). RESULTS: Significant differences in TUG test scores across conditions were observed in both DMD and typical development groups (p < 0.05). Children with DMD exhibited longer completion times compared to typical development children (p < 0.05). Among children with DMD, there was a significant correlation between TUG scores in different task conditions and balance assessment (p < 0.05, r = 0.571 to -0.819). Lower MFM-32 scores in DMD children were correlated with worse TUG performance across conditions (p < 0.05, r = 0.586 to -0.868). SIGNIFIANCE: This study sheds light on the multifaceted nature of dual-tasking challenges in individuals with DMD, thereby contributing to a deeper understanding of the implications for rehabilitation strategies.

Anaemia-based screening for resistance to thyroid hormone alpha in children.

BACKGROUND: The hypothyroid phenotype associated with resistance to thyroid hormone alpha (RTH-α) is associated with a diverse clinical picture. On the other hand, thyroid-stimulating hormone (TSH) levels are normal. Free triiodothyronine (fT3) and free thyroxine (fT4) levels can also be normal; however, normo- or macrocytic anaemia is usually present in reported cases. Diagnosis is challenging and there is limited data regarding screening methods. OBJECTIVE: The study aimed to assess the efficiency of a screening strategy for RTH-α. SUBJECTS AND METHODS: Out of a total of 6540 children evaluated at the outpatient clinics of paediatric neurology over 2 years and who underwent complete blood count and thyroid function tests, 432 were found to have anaemia. Within this group, we identified 42 children without an underlying specific neurological aetiology who exhibited normo- or macrocytic anaemia, normal TSH levels, fT3 levels in the upper half of the normal range or high, and fT4 levels in the lower half of the normal range or low. We excluded one patient who had already been diagnosed with RTH-α and nine patients could not be reached. Subsequently, clinical evaluation, biochemical assessment, and THRA sequencing analysis were conducted on 32 children. The findings were compared with those of the known RTH-α patients in our unit. RESULTS: The median age of the patients was 5.7 (5.1-7.4) years, and 22 of them were males (69%). The main reasons for assessment in paediatric neurology clinics were autism spectrum disorder (n = 12, 38%), epilepsy (n = 11, 34%), and delay in developmental stages (n = 8, 25%). Constipation was present in five of the cases (16%), while the closure of the anterior fontanelle and tooth eruption were delayed in two cases (6%) and one case (3%), respectively. The median length/height and weight standard deviation (SD) scores were 0.3 [(-0.8)-(1.1)] and -0.1 [(-0.8)-(0.3)], respectively. The median fT3, fT4, and TSH levels were 4.6 (4.2-5.0) pg/mL, 0.9 (0.8-1.0) ng/dL, and 2.2 (1.8-3.1) uIU/mL, respectively. Thirteen of the patients (41%) had high fT3 levels, while none of them had low fT4 levels. The normo- or macrocytic anaemia rate was 47% (normocytic/macrocytic, n = 8/7) at the time of reassessment. Serum creatine kinase (CK) was elevated in five patients (16%; one had anaemia). None of the subjects had a pathological variant in THRA. Known RTH-α patients had significantly lower median height SD score, higher rates of delayed tooth eruption and closure of the anterior fontanelle, lower haemoglobin levels, and higher mean corpuscular volume (MCV) and CK levels as compared to those found without RTH-α. CONCLUSIONS: This approach found one known patient with RTH-α but did not reveal any new cases. Notably, normo- or macrocytic anaemia did not persist in nearly half of the screened patients. A screening strategy that takes clinical findings and prominent laboratory features suggestive of RTH-α into account could lower unnecessary genetic analysis of THRA in patients presenting with neurological problems.

Optic neuritis in Turkish children and adolescents: A multicenter retrospective study.

BACKGROUND: Various etiologies may underlie optic neuritis, including autoantibody-mediated disorders described in the last decade. We re-examined demographic, clinical, laboratory features and prognostic factors in pediatric patients with autoimmune optic neuritis according to current knowledge. METHODS: Cases of pediatric ON from 27 centers in Türkiye diagnosed between 2009 and 2022 were included for retrospective evaluation. RESULTS: The study included 279 patients, 174 females and 105 males, with a female-to-male ratio of 1.65. The average age at onset was 12.8 ± 3.4 years, and mean follow-up, 2.1 years (range: 1-12.1 years). Patients <10 years old were grouped as "prepubertal" and those ≥10 years old as "others". The diagnoses made at the end of follow-up were multiple sclerosis associated optic neuritis (n = 90, 32.3 %), single isolated optic neuritis (n = 86, 31 %), clinically isolated syndrome (n = 41, 14.7 %), myelin oligodendrocyte glycoprotein antibody associated optic neuritis (n = 22, 7.9 %), and relapsing isolated optic neuritis (n = 18, 6.5 %). Predominant diagnoses were myelin oligodendrocyte glycoprotein antibody associated optic neuritis and acute disseminated encephalomyelitis associated optic neuritis in the prepubertal group and multiple sclerosis associated optic neuritis in the older group. Recurrences were observed in 67 (24 %) patients, including 28 with multiple sclerosis associated optic neuritis, 18 with relapsing isolated optic neuritis, 11 with myelin oligodendrocyte glycoprotein antibody associated optic neuritis, 8 with aquaporin-4 antibody related optic neuritis, and 2 with chronic relapsing inflammatory optic neuropathy. Recurrences were more common among female patients. Findings supporting the diagnosis of multiple sclerosis included age of onset ≥ 10 years (OR=1.24, p = 0.027), the presence of cranial MRI lesions (OR=26.92, p<0.001), and oligoclonal bands (OR=9.7, p = 0.001). Treatment in the acute phase consisted of intravenous pulse methylprednisolone (n = 46, 16.5 %), pulse methylprednisolone with an oral taper (n = 212, 76 %), and combinations of pulse methylprednisolone, plasmapheresis, or intravenous immunoglobulin (n = 21, 7.5 %). Outcome at 12 months was satisfactory, with 247 out of 279 patients (88.5 %) demonstrating complete recovery. Thirty-two patients exhibited incomplete recovery and further combination treatments were applied. Specifically, patients with relapsing isolated optic neuritis and aquaporin-4 antibody related optic neuritis displayed a less favorable prognosis. CONCLUSION: Our results suggest optic neuritis is frequently bilateral in prepubertal and unilateral in peri­ or postpubertal patients. Age of onset 10 or older, presence of oligoclonal bands, and brain MRI findings reliably predict the development of multiple sclerosis. The risk of developing multiple sclerosis increases mostly during the second and third years of follow-up. Relapsing isolated optic neuritis remains a separate group where the pathogenesis and outcome remain unclear. Investigation of predisposing and diagnostic biomarkers and long follow-up could help to define this group.

Evaluation of risk factors for recurrence of cutaneous adverse reactions due to anti-seizure medications in children: A retrospective study.

Background: Cutaneous adverse reactions (CARs) are one of the most important reasons for anti-seizure medication (ASM) discontinuation in epilepsy. However, such discontinuations can cause an increase in seizures. This study investigates the risk factors for ASM-related rash recurrence in children. Methods: This retrospective case-control study consisted of the patient group with a single rash due to ASMs (group 1), the patient group with rash recurrence (group 2), and the control group. While the demographic and clinical features of group 1 and the control group were compared in terms of a single rash, group 1 and group 2 were compared for rash recurrence. Results: Group 1, group 2, and control group consisted of 112, 33, and 166 patients, respectively. Female gender was a risk factor for a single rash (P < 0.001) but not for recurrence (P = 0.439). Presence of atopic disease [odds ratio (OR): 9.5, 95% confidence interval (CI): 3.8-23.1, P < 0.001], family history of drug allergy (OR: 26.3, 95% CI: 9.6-72.1, P < 0.001), and polytherapy (OR: 23.5, 95% CI: 8.7-62.9, P < 0.001) were risk factors for rash recurrence. Aromatic nature of both the ASMs associated with the first rash (OR: 14.4, 95% CI: 3.2-63.2, P < 0.001) and rash recurrence (OR: 11.3, 95% CI: 4.6-27.5, P < 0.001) were determined as risk factors separately. Conclusion: Careful use of aromatic drugs may prevent recurrence of ASM-related CAR in children, particularly in cases of personal history of allergic disease and family history of drug allergy.