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Objectives: The purpose of this study is to evaluate the validity of the standard approach in expert judgment for evaluating precision medicines, in which experts are required to estimate outcomes as if they did not have access to diagnostic information, whereas in fact, they do., Methods: Fourteen clinicians participated in an expert judgment task to estimate the cost and medical outcomes of the use of exome sequencing in pediatric patients with intractable epilepsy in Thailand. Experts were randomly assigned to either an "unblind" or "blind" group; the former was provided with the exome sequencing results for each patient case prior to the judgment task, whereas the latter was not provided with the exome sequencing results. Both groups were asked to estimate the outcomes for the counterfactual scenario, in which patients had not been tested by exome sequencing., Results: Our study did not show significant results, possibly due to the small sample size of both participants and case studies., Conclusions: A comparison of the unblind and blind approach did not show conclusive evidence that there is a difference in outcomes. However, until further evidence suggests otherwise, we recommend the blind approach as preferable when using expert judgment to evaluate precision medicines because this approach is more representative of the counterfactual scenario than the unblind approach.

Muscular dystrophies and congenital myopathies are heterogeneous groups of inherited muscular disorders. An accurate diagnosis is challenging due to their complex clinical presentations and genetic heterogeneity. This study aimed to determine the utilisation of exome sequencing (ES) for Thai paediatric patients with muscular disorders. Of 176 paediatric patients suspected of genetic/inherited myopathies, 133 patients received a molecular diagnosis after performing conventional investigations, single gene testing, and gene panels. The remaining 43 patients from 42 families could be classified into three groups: Group 1, MLPA-negative Duchenne muscular dystrophy (DMD) with 9 patients (9/43; 21%), Group 2, other muscular dystrophies (MD) with 18 patients (18/43; 42%) and Group 3, congenital myopathies (CM) with 16 patients (16/43; 37%). All underwent exome sequencing which could identify pathogenic variants in 8/9 (89%), 14/18 (78%), and 8/16 (50%), for each Group, respectively. Overall, the diagnostic yield of ES was 70% (30/43) and 36 pathogenic/likely pathogenic variants in 14 genes were identified. 18 variants have never been previously reported. Molecular diagnoses provided by ES changed management in 22/30 (73%) of the patients. Our study demonstrates the clinical utility and implications of ES in inherited myopathies., (© 2023. The Author(s).)

Background: Neuronal ceroid lipofuscinoses (NCLs) (hereafter described as CLN disease) comprise a rare and life-limiting set of genetically inherited neurodegenerative disorders that are characterized by abnormal lysosomal storage. The NCL disorders are, collectively, the most common group of degenerative brain disorders in children., Patient Descriptions: We report two cases of CLN disease that were diagnosed and treated at the Department of Pediatrics, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand. Both cases of CLN disease (CLN1 and CLN6 diagnosed in 2016 and 2017, respectively) profiled in this report presented with clinical features of Rett syndrome. In the first case, a 2-year-old girl presented with Rett-like clinical features, including global developmental regression and hand-wringing action. Single-gene analysis of the MECP2 gene was negative. However, PPT1 gene sequencing revealed a novel homozygous frameshift mutation, c.629_630dupGT (p.Ile211Valfs∗10). In the second case, a 7.5-year-old girl presented with ataxia, progressive myoclonic epilepsy, and Rett-like hand-wringing. A c.794_796delCCT variant in the CLN6 gene was identified by whole-exome sequencing. Fingerprint bodies from electron microscopy of the skin also supported a diagnosis of CLN disease in our second case., Discussion: Presentation with clinical features of Rett syndrome has only been reported in patients diagnosed with CLN1 and CLN7 disease, and never in those with CLN6., Conclusions: Physicians should suspect and investigate for CLN disease in patients with Rett-like phenotype who are negative for MECP2 mutation, especially in patients with visual impairment and early prominent brain atrophy., (Copyright © 2022 Elsevier Inc. All rights reserved.)

The use of rapid DNA sequencing technology in severely ill children in developed countries can accurately identify diagnoses and positively impact patient outcomes. This study sought to evaluate the outcome of Thai children and adults with unknown etiologies of critical illnesses with the deployment of rapid whole exome sequencing (rWES) in Thailand. We recruited 54 unrelated patients from 11 hospitals throughout Thailand. The median age was 3 months (range, 2 days-55 years) including 47 children and 7 adults with 52% males. The median time from obtaining blood samples to issuing the rWES report was 12 days (range, 5-27 days). A molecular diagnosis was established in 25 patients (46%), resulting in a change in clinical management for 24 patients (44%) resulting in improved clinical outcomes in 16 patients (30%). Four out of seven adult patients (57%) received the molecular diagnosis which led to a change in management. The 25 diagnoses comprised 23 different diseases. Of the 34 identified variants, 15 had never been previously reported. This study suggests that use of rWES as a first-tier investigation tool can provide tremendous benefits in critically ill patients with unknown etiology across age groups in Thailand., (© 2021 John Wiley & Sons A/S . Published by John Wiley & Sons Ltd.)

Congenital myasthenic syndromes (CMS) comprise a heterogeneous group of genetic disorders of the neuromuscular junction. Next generation sequencing has been increasingly used for molecular diagnosis in CMS patients. This study aimed to identify the disease-causing variants in Thai patients. We recruited patients with a diagnosis of CMS based on clinical and electrophysiologic findings, and whole exome sequencing was performed. Thirteen patients aged from 2 to 54 years (median: 8 years) from 12 families were enrolled. Variants were identified in 9 of 13 patients (69%). Five novel variants and two previously reported variant were found in the COLQ, RAPSN and CHRND gene. The previously reported c.393+1G>A splice site variant in the COLQ gene was found in a majority of patients. Five patients harbor the homozygous splice site c.393+1G>A variant, and two patients carry compound heterozygous c.393+1G>A, c.718-1G>T, and c.393+1G>A, c.865G>T (p.Gly289Ter) variants. The novel variants were also found in RAPSN (p.Cys251del, p.Arg282Cys) and CHRND (p.Met481del). Molecular diagnosis in CMS patients can guide treatment decisions and may be life changing, especially in patients with COLQ mutations., (Copyright © 2020 Elsevier B.V. All rights reserved.)