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Charcot-Marie-Tooth (CMT) is a group of inherited neuromuscular disorders with diverse clinical features such as muscle weakness and atrophy of the distal regions, foot deformities, sensory loss and decreased or absent reflexes. With the diverse inheritance patterns including dominant, recessive, and X-linked, it exhibits significant genetic heterogeneity often overlapping with other neurological disorders. Whole exome sequencing (WES) has emerged as favorable diagnostic tool for such challenging disease entities. We recruited five Pakistani families that consisted of 14 affected individuals exhibiting representative symptoms of CMT such as severe muscle weakness of the lower limbs, muscles atrophy, claw hands and feet deformities. WES data analysis revealed two novel and two already reported homozygous missense variants in GDAP1 (NM_018972) c.1A > G (p. Met1Val), c.683A > G (p. Glu228Gly), c.734C > T (p. Thr245Ile) and c.811G > A (p. Gly271Arg) in families A-D, respectively. While a novel homozygous SBF2 variant c.2746G > C, p. (Gly916Arg) was identified in family E. Sanger sequencing confirm the segregation of all candidate variants in their respective pedigrees. Moreover, molecular modeling supports the destabilizing effect of these variants on final protein product of both GDAP1 and SBF2 by inducing modifications in overall conformation of the protein. The present study expands the mutation spectrum of the GDAP1 and SBF2 genes, with possible implications for improved understanding of disease pathophysiology. Furthermore, the current study highlights the importance of NGS, particularly WES, in achieving rapid and precise molecular genetic diagnosis for clinical purposes, especially in neuromuscular disorders of heterogeneous nature.

Plasma proteomic profiling of 92 individuals with Post-Acute Sequelae of SARS-CoV-2 infection (PASC), assessed a mean of 34 months after acute infection, revealed a distinct inflammatory signature. Using proximity extension assay technology, 358 proteins were quantified, identifying 26 differentially expressed proteins (DEPs) in PASC: 23 upregulated and 3 downregulated. The most upregulated proteins were Oncostatin M (OSM) and IL-1 receptor antagonist (IL1RN). Additional increases were observed in IL-6, IL-12B, IL-2, CCL22, CSF3, CSF1, and HLA-DRA, as well as proteins involved in tissue remodeling and angiogenesis such as ANGPTL2 and TGFA. Random forest analysis confirmed IL1RN, OSM, ANGPTL2, HLA-DRA, and CLEC4A as strong discriminators between patients and controls. Gene set enrichment analysis demonstrated activation of multiple immune pathways, including Inflammatory Response, TNF-alpha/NF-kappa B signaling, IL-6/JAK/STAT3, IL-2/STAT5, and Allograft Rejection, indicating persistent activation of innate and adaptive immunity. STRING network analysis highlighted a tightly connected cytokine-driven inflammatory module. Plasma spike protein levels did not differ between patients and controls, suggesting that PASC-related inflammation may persist independently of ongoing viral replication. Overall, the findings indicate a consistent low-grade inflammatory state in PASC without evidence for distinct biological subtypes.

Background: Post-acute sequelae of SARS-CoV-2 infection (PASC), also known as post-COVID-19 condition (here abbreviated as post-COVID) is an escalating global health issue. The aim of our study was to investigate the mechanisms and clinical manifestations of post-COVID following a mild SARS-CoV-2 infection.

Methods: We analyzed the gene expression profile in PBMCs from 60 middle-aged post-COVID patients and 50 age-matched controls at a median time of 28 months following a mild SARS-CoV-2 infection. The clinical assessments included intensity of post-COVID symptoms, physical and mental fatigue, depression and anxiety. Sixty-seven participants performed a mild exertion ergometer test with assessment of lactate concentrations. Transcriptome analysis was performed on mRNA selected by poly-A enrichment and SARS-CoV-2 RNA fragments were analyzed using the ARTIC protocol.

Results: We identified 463 differentially expressed transcripts in PBMCs, of which 324 were upregulated and 129 downregulated in post-COVID patients. Upregulated genes in post-COVID individuals were enriched for processes involving JAK-STAT signaling, negative regulation of ubiquitination, IL9 signaling, and negative regulation of viral process, suggesting chronic inflammation. Downregulated genes were enriched for processes involving mitochondrial ATP synthesis, and oxidative phosphorylation, suggesting mitochondrial dysfunction. No SARS-CoV-2 gene fragments were detected in PBMCs of patients with post-COVID and no IFN genes were found differentially expressed in post-COVID patients. Post-COVID was associated with elevated lactate levels in blood, both at rest and after a short recovery phase following exertion, suggesting increased anaerobic activity in skeletal muscles. We did not find differences in the transcriptional profiles or clinical manifestations when comparing patients who contracted the infection from early SARS-CoV-2 variants with those who contracted the infection during the period when the Omicron variant was prevalent.

Conclusions: Our findings highlight molecular changes compatible with a persistent immune response in PBMCs of post-COVID subjects at a median follow-up of 28 months after a mild infection, supporting the hypothesis that post-COVID is a chronic inflammatory condition. The upregulation of JAK/STAT signaling suggests a potential therapeutic target in post-COVID.

Dravet syndrome (DS) is a devastating early-onset refractory epilepsy syndrome caused by variants in the SCN1A gene. A disturbed GABAergic interneuron function is implicated in the progression to DS but the underlying developmental and pathophysiological mechanisms remain elusive, in particularly at the chromatin level. Induced pluripotent stem cells (iPSCs) derived from DS cases and healthy donors were used to model disease-associated epigenetic abnormalities of GABAergic development. Chromatin accessibility was assessed at multiple time points (Day 0, Day 19, Day 35, and Day 65) of GABAergic differentiation. Additionally, the effects of the commonly used anti-seizure drug valproic acid (VPA) on chromatin accessibility were elucidated in GABAergic cells. The distinct dynamics in the chromatin profile of DS iPSC predicted accelerated early GABAergic development, evident at D19, and diverged further from the pattern in control iPSC with continued differentiation, indicating a disrupted GABAergic maturation. Exposure to VPA at D65 reshaped the chromatin landscape at a variable extent in different iPSC-lines and rescued the observed dysfunctional development of some DS iPSC-GABA. The comprehensive investigation on the chromatin landscape of GABAergic differentiation in DS-patient iPSC offers valuable insights into the epigenetic dysregulations associated with interneuronal dysfunction in DS. Moreover, the detailed analysis of the chromatin changes induced by VPA in iPSC-GABA holds the potential to improve the development of personalized and targeted anti-epileptic therapies.

Methods One severely affected individual underwent thorough investigation with neurophysiological and blood pressure (BP) measurements, including direct recording of baroreflex-governed sympathetic nerve signalling and induction of BP rise with phenylephrine. Family members underwent parts of the examination. Genetic analysis using exome sequencing was performed.

Results Marked postural hypotension with greatly reduced cardiac preload was observed, but without signs of autonomic nervous system dysfunction: sympathetic nerve signalling was normal, as were catecholamine levels, and phenylephrine stimulation revealed a normal increase in BP. The results of the genetic analysis using exome sequencing comprising all known genes associated with the regulation of BP and catecholamine metabolism were normal.

Conclusion The combined findings suggest an autosomal dominant form of early-onset orthostatic hypotension with variable clinical expression and without any additional autonomic dysfunction. It is possible that further investigation will reveal an as yet undescribed entity of orthostatic hypotension transmitted as an autosomal dominant trait.

Spinocerebellar disorders are a vast group of rare neurogenetic conditions, generally characterized by overlapping clinical symptoms including progressive cerebellar ataxia, spastic paraparesis, cognitive deficiencies, skeletal/muscular and ocular abnormalities. The objective of the present study is to identify the underlying genetic causes of the rare spinocerebellar disorders in the Pakistani population. Herein, nine consanguineous families presenting different spinocerebellar phenotypes have been investigated using whole exome sequencing. Sanger sequencing was performed for segregation analysis in all the available individuals of each family. The molecular analysis of these families identified six novel pathogenic/likely pathogenic variants; ZFYVE26: c.1093del, SACS: c.1201C>T, BICD2: c.2156A>T, ALS2: c.2171-3T>G, ALS2: c.3145T>A, and B4GALNT1: c.334_335dup, and three already reported pathogenic variants; FA2H: c.159_176del, APTX: c.689T>G, and SETX: c.5308_5311del. The clinical features of all patients in each family are concurrent with the already reported cases. Hence, the current study expands the mutation spectrum of rare spinocerebellar disorders and implies the usefulness of next-generation sequencing in combination with clinical investigation for better diagnosis of these overlapping phenotypes.

Purpose The rationale behind the SUDden cardiac Death in the Young (SUDDY) cohort was to provide a complete nationwide, high-quality platform with integrated multisource data, for clinical and genetic research on sudden cardiac death (SCD) in the young, with the ultimate goal to predict and prevent SCD. Participants The cohort contains all SCD victims <36 years, in Sweden during the period 2000-2010. We assigned five population-based controls per case, together with parents of cases and controls, in total 15 633 individuals. Data of all individuals were extracted from multiple mandatory registries; the National Patient Registry, the Medical Birth Registry, the Prescribed Drug registry, the Cause of Death registry, the Multigeneration Registry, combined with socioeconomic data from Statistics Sweden. From SCD victims, the autopsy report, medical records, ECGs, parental information and biological samples were gathered. Findings to date We identified 903 individuals diagnosed with SCD (67% men, 33% women). The cases comprised 236 infants <1 year of age (26%), 90 individuals aged 1-15 years (10%), 186 individuals aged 15-25 years (21%) and 391 aged 25-35 years (43%). Hospitalisations and outpatient clinic visits due to syncope were significantly more common among cases than controls. DNA obtained from dried blood spots tests (DBS) stored from birth was equally suitable as venous blood samples for high-throughput genetic analysis of SCD cases. Future plans We will explore the SUDDY cohort for symptoms and healthcare consumption, socioeconomic variables and family history of SCD. Furthermore, we will perform whole exome sequencing analysis on DNA of cases obtained from DBS or postmortem samples together with parental blood samples in search for gene variants associated with cardiac disease. The genetic analysis together with data compiled in the nationwide cohort is expected to improve current knowledge on the incidence, aetiology, clinical characteristics and family history of SCD.

Dravet syndrome is an early onset devastating epilepsy syndrome usually caused by heterozygous mutations in SCN1A. We generated a human iPSC line (UUIGPi015A) from dermal fibroblasts of a patient with Dravet syndrome carrying a deletion on chromosome 2 encompassing SCN1A and 9 flanking genes. Characterization of the iPSC line confirmed expression of pluripotency markers, tri-lineage differentiation capacity and absence of exogenous reprogramming factors. The iPSC line retained the deletion and was genomically stable. The iPSC line UUIGPi015-A provides a useful resource for studies on the pathophysiology of Dravet syndrome and seizures caused by haploinsufficiency of SCN1A and flanking gene products.

Fibromyalgia (FM) is an idiopathic chronic disease characterized by widespread musculoskeletal pain, hyperalgesia and allodynia, often accompanied by fatigue, cognitive dysfunction and other symptoms. Autoimmunity and neuroinflammatory mechanisms have been suggested to play important roles in the pathophysiology of FM supported by recently identified interferon signatures in affected individuals. However, the contribution of different components in the immune system, such as the B-lymphocytes, in the progression to FM are yet unknown. Furthermore, there is a great need for biomarkers that may improve diagnostics of FM. Herein, we investigated the gene expression profile in peripheral B-cells, as well as a panel of inflammatory serum proteins, in 30 FM patients and 23 healthy matched control individuals. RNA sequence analysis revealed 60 differentially expressed genes when comparing the two groups. The group of FM patients showed increased expression of twenty-five interferon-regulated genes, such as S100A8 and S100A9, VCAM, CD163, SERPINA1, ANXA1, and an increased interferon score. Furthermore, FM was associated with elevated levels of 19 inflammatory serum proteins, such as IL8, AXIN1, SIRT2 and STAMBP, that correlated with the FM severity score. Together, the results shows that FM is associated with an interferon signature in B-cells and increased levels of a set of inflammatory serum proteins. Our findings bring further support for immune activation in the pathogenesis of FM and highlight candidate biomarkers for diagnosis and intervention in the management of FM.