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Background We aimed to determine whether sodium valproate (VPA) should be contraindicated in all mitochondrial diseases, due to known VPA-induced severe hepatotoxicity in some mitochondrial diseases.Methods We systematically reviewed the published literature for mitochondrial DNA (mtDNA) and common nuclear genotypes of mitochondrial diseases using PubMed, Ovid Embase, Ovid Medline and MitoPhen databases. We extracted patient-level data from peer-reviewed articles, published until July 2022, using the Human Phenotype Ontology to manually code clinical presentations for 156 patients with genetic diagnoses from 90 publications.Results There were no fatal adverse drug reactions (ADRs) in the mtDNA disease group (35 patients), and only 1 out of 54 patients with a non-POLG mitochondrial disease developed acute liver failure. There were fatal outcomes in 53/102 (52%) POLG VPA-exposed patients who all harboured recessive mutations.Conclusions Our findings confirm the high risk of severe ADRs in any patient with recessive POLG variants irrespective of the phenotype, and therefore recommend that VPA is contraindicated in this group. However, there was limited evidence of toxicity to support a similar recommendation in other genotypes of mitochondrial diseases.

Introduction Acne is one of the most common inflammatory skin diseases worldwide and can have significant psychosocial impact and cause permanent scarring. Spironolactone, a potassium-sparing diuretic, has antiandrogenic properties, potentially reducing sebum production and hyperkeratinisation in acne-prone follicles. Dermatologists have prescribed spironolactone for acne in women for over 30 years, but robust clinical study data are lacking. This study seeks to evaluate whether spironolactone is clinically effective and cost-effective in treating acne in women.Methods and analysis Women (≥18 years) with persistent facial acne requiring systemic therapy are randomised to receive one tablet per day of 50 mg spironolactone or a matched placebo until week 6, increasing to up to two tablets per day (total of 100 mg spironolactone or matched placebo) until week 24, along with usual topical therapy if desired. Study treatment stops at week 24; participants are informed of their treatment allocation and enter an unblinded observational follow-up period for up to 6 months (up to week 52 after baseline). Primary outcome is the Acne-specific Quality of Life (Acne-QoL) symptom subscale score at week 12. Secondary outcomes include Acne-QoL total and subscales; participant acne self-assessment recorded on a 6-point Likert scale at 6, 12, 24 weeks and up to 52 weeks; Investigator’s Global Assessment at weeks 6 and 12; cost and cost effectiveness are assessed over 24 weeks. Aiming to detect a group difference of 2 points on the Acne-QoL symptom subscale (SD 5.8, effect size 0.35), allowing for 20% loss to follow-up, gives a sample size of 398 participants.Ethics and dissemination This protocol was approved by Wales Research Ethics Committee (18/WA/0420). Follow-up to be completed in early 2022. Findings will be disseminated to participants, peer-reviewed journals, networks and patient groups, on social media, on the study website and the Southampton Clinical Trials Unit website to maximise impact.Trial registration number ISRCTN12892056;Pre-results.

Objective To explore current communication practices for positive newborn screening results from the newborn bloodspot screening (NBS) laboratory to clinicians to highlight differences, understand how the pathways are implemented in practice, identify barriers and facilitators and make recommendations for future practice and research.Design A qualitative exploratory design was employed using semi-structured interviews.Setting Thirteen NBS laboratories in England.Participants Seventy-one clinicians; 22 NBS laboratory staff across 13 laboratories and 49 members of relevant clinical teams were interviewed.Results Assurance of quality and consistency was a priority for all NBS laboratories. Findings indicated variation in approaches to communicating positive NBS results from laboratories to clinical teams. This was particularly evident for congenital hypothyroidism and was largely influenced by local arrangements, resources and the fact individual laboratories had detailed standard operating procedures for how they work. Obtaining feedback from clinical teams to the laboratory after the child had been seen could be challenging and time-consuming for those involved. Pathways for communicating carrier results for cystic fibrosis and sickle cell disease could be ambiguous and inconsistent which in turn could hamper the laboratories efforts to obtain timely feedback regarding whether or not the result had been communicated to the family. Communication pathways for positive NBS results between laboratories and clinical teams could therefore be time-consuming and resource-intensive.Conclusion The importance placed on ensuring positive NBS results were communicated effectively and in a timely fashion from the laboratory to the clinical team was evident from all participants. However, variation existed in terms of the processes used to report positive NBS results to clinical teams and the people involved. Variant practice identified may reflect local needs, but more often reflected local resources and a more consistent ‘best practice’ approach is required, not just in the UK but perhaps globally.Trial registration number ISRCTN15330120.

Objective To explore health professionals’ experiences of communicating positive newborn bloodspot screening (NBS) results, highlight differences, share good practice and make recommendations for future research.Design Qualitative exploratory design was employed using semi-structured interviewsSetting Three National Health Service provider organisations in EnglandParticipants Seventeen health professionals involved in communicating positive newborn bloodspot screening results to parents for all nine conditions currently included in the newborn bloodspot screening programme in England.Results Findings indicated variation in approaches to communicating positive newborn bloodspot screening results to parents, largely influenced by resources available and the lack of clear guidance. Health professionals emphasised the importance of communicating results to families in a way that is sensitive to their needs. However, many challenges hindered communication including logistical considerations; difficulty contacting the family and other health professionals; language barriers; parental reactions; resource considerations; lack of training; and insufficient time.Conclusion Health professionals invest a lot of time and energy trying to ensure communication of positive newborn bloodspot screening results to families is done well. However, there continues to be great variation in the way these results are communicated to parents and this is largely influenced by resources available but also the lack of concrete guidance. How best to support health professionals undertaking this challenging and emotive task requires further exploration. We recommend evaluation of a more cohesive approach that meets the needs of parents and staff while being sensitive to the subtleties of each condition.Trial registration number ISRCTN15330120

Following the discovery in the early 1960s that mitochondria contain their own DNA (mtDNA), there were two major advances, both in the 1980s: the human mtDNA sequence was published in 1981, and in 1988 the first pathogenic mtDNA mutations were identified. The floodgates were opened, and the 1990s became the decade of the mitochondrial genome. There has been a change of emphasis in the first few years of the new millennium, away from the "magic circle" of mtDNA and back to the nuclear genome. Various nuclear genes have been identified that are fundamentally important for mitochondrial homeostasis, and when these genes are disrupted, they cause autosomally inherited mitochondrial disease. Moreover, mitochondrial dysfunction plays an important role in the pathophysiology of several well established nuclear genetic disorders, such as dominant optic atrophy (mutations in OPA1), Friedreich's ataxia (FRDA), hereditary spastic paraplegia (SPG7), and Wilson's disease (ATP7B). The next major challenge is to define the more subtle interactions between nuclear and mitochondrial genes in health and disease. [ABSTRACT FROM AUTHOR]

The article focuses on the aspects of whole exome sequencing such as its mechanisms, its use in neurology, and its benefits. It states that second generation sequencing allows DNA to be sequenced faster, providing cost benefits in genetic analysis. It presents a case which shows how to identify pathogenic mutations in a family. It adds that second generation sequencing is restricted by its limited ability to discover DNA rearrangements and expansion disorders. INSET: Glossary of terms.

A 39-year-old woman presented to the neurology clinic with an abnormal gait. Subsequent investigations confirmed a rare neurodegenerative disease. This case highlights the key clinical features and diagnostic approach to neuroferritinopathy, and describes the discovery of the disease in a family from Cumbria in the north west of England. INSET: PRACTICE POINTS. [ABSTRACT FROM AUTHOR]

Background: The POLG1 gene encodes the catalytic subunit of DNA polymerase gamma, essential for mitochondrial DNA replication and repair. Mutations in POLG1 have been linked to a spectrum of clinical phenotypes, and may account for up to 25% of all adult presentations of mitochondrial disease. Methods and results: We present 14 patients, with characteristic features of mitochondrial disease including progressive external ophthalmoplegia (PEO) and Alpers-Huttenlocher syndrome and laboratory findings indicative of mitochondrial dysfunction, including cytochrome c oxidase (COX) deficiency and multiple deletions or depletion of the mitochondrial DNA. Four novel POLG1 missense substitutions (p.R597W, p.L605R, p.G746S, p.A862T), are described, together with the first adult patient with a recently described polymerase domain mutation (p.R1047W). All novel changes were rare in a control population and affected highly conserved amino acids. Conclusion: The addition of these substitutions--including the first report of a dinucleotide mutation (c.1814‗1815TT>GC)--to the growing list of defects further confirms the importance of POLG1 mutations as the underlying abnormality in a range of neurological presentations. [ABSTRACT FROM AUTHOR]

Leber hereditary optic neuropathy (LHON) and autosomal dominant optic atrophy (DOA) are the two most common inherited optic neuropathies and they result in significant visual morbidity among young adults. Both disorders are the result of mitochondrial dysfunction: LHON from primary mitochondrial DNA (mtDNA) mutations affecting the respiratory chain complexes; and the majority of DOA families have mutations in the OPA1 gene, which codes for an inner mitochondrial membrane protein critical for mtDNA maintenance and oxidative phosphorylation. Additional genetic and environmental factors modulate the penetrance of LHON, and the same is likely to be the case for DOA which has a markedly variable clinical phenotype. The selective vulnerability of retinal ganglion cells (RGCs) is a key pathological feature and understanding the fundamental mechanisms that underlie RGC loss in these disorders is a prerequisite for the development of effective therapeutic strategies which are currently limited. [ABSTRACT FROM AUTHOR]

Introduction: Autosomal dominant optic atrophy (ADOA) is considered as the most common form of hereditary optic neuropathy. Although genetic linkage studies point to the OPA1 locus on chromosome 3q28-q29 as by far the most common gene locus, previous screening studies--based on sequencing of the coding exons--detected OPA1 mutations in only 32-70% of ADOA patients. We therefore hypothesised that larger deletions or duplications that remained undetected in previous screening approaches may substantially contribute to the prevalence of OPA1 mutations in ADOA. Methods: 42 independent ADOA patients were analysed for the presence of genomic rearrangements in OPA1 by means of multiplex ligation probe amplification (MLPA). Deletions or duplications were confirmed either by long distance polymerase chain reaction (PCR) and breakpoint sequencing or loss of heterozygosity analyses with flanking microsatellite markers. Patients underwent ophthalmological examination including visual acuity, colour vision testings, perimetry and funduscopy. Results: We identified genomic rearrangements in 8 of 42 patients, including single exon deletions of exon 9 and exon 24, respectively, a deletion of exons 1-5, two different deletions of the complete OPA1 gene as well as a duplication of the exons 7-9, with the latter being present in three unrelated families. Patients' phenotypes were highly variable, similar to patients with point mutation in OPA1. Discussion: Our findings show that gross genomic aberrations at the OPA1 gene locus are frequent in ADOA and substantially contribute to the spectrum and prevalence of OPA1 mutations in ADOA patients. They further strengthen the hypothesis that haploinsufficiency is a major pathomechanism in OPA1 associated ADOA. [ABSTRACT FROM AUTHOR]

Leber hereditary optic neuropathy (LHON) is a mitochondrial genetic disease that preferentially causes blindness in young adult males, affecting about 1 in 25 000 of the British population. It is characterised by bilateral subacute loss of central vision owing to focal degeneration of the retinal ganglion cell layer and optic nerve. Over 95% of LHON cases are primarily the result of one of three mitochondrial DNA (mtDNA) point mutations, G3460A, G11778A, and T14484C, which all involve genes encoding complex I subunits of the respiratory chain. An intriguing feature of LHON is that only ∼50% of males and ∼10% of females who harbour a pathogenic mtDNA mutation actually develop the optic neuropathy. This marked incomplete penetrance and gender bias imply that additional mitochondrial and/or nuclear genetic factors must be modulating the phenotypic expression of LHON. It is also likely that environmental factors contribute to the onset of visual failure. However, these secondary precipitating factors remain poorly defined at present. In this review, we describe the natural history of this optic nerve disorder and highlight issues relating to clinical diagnosis, management, and genetic counselling. We also discuss the findings of recently published studies and the light they shed on the complex aetiology and pathophysiology of LHON. [ABSTRACT FROM AUTHOR]

Having excluded common structural, inflammatory and vascular causes of a spastic paraparesis, the diagnostic yield of further clinical investigations is low. Here, we show that testing for rare metabolic and genetic causes can have important implications for both the patient and their family. [ABSTRACT FROM AUTHOR]

Background: Insulin resistance and hyperglycaemia are common in severe sepsis. Mitochondrial uncoupling protein 2 (UCP2) plays a role in insulin release and sensitivity. Objectives: To determine if a common, functional polymorphism in the UCP2 gene promoter region (the ?'866 G/A polymorphism) contributes to the risk of hyperglycaemia in severe sepsis. Results: In the prospective group 120 non-diabetic patients who were carriers of the G allele had significantly higher maximum blood glucose recordings than non-carriers (mean (SD) AA 8.5 (2.2) mmol/l; GA 8.5 (2.4) mmol/l; GG 10.1 (3.1) mmol/l; p?=?0.0042) and required significantly more insulin to maintain target blood glucose (p?=?0.0007). In the retrospective study 103 non-diabetic patients showed a similar relationship between maximum glucose and UCP genotype (AA 6.8 (2.3) mmol/l; GA 7.8 (2.2) mmol/l; GG 9.2 (2.9) mmol/l; p?=?0.0078). Conclusions: A common, functional polymorphism in the promoter region of the UCP2 gene is associated with hyperglycaemia and insulin resistance in severe sepsis. This has implications for our understanding of the genetic pathophysiology of sepsis and is of use in the stratification of patients for more intensive management. [ABSTRACT FROM AUTHOR]

We report the case of a 2-year-old boy with seizures who developed hepatic failure shortly after commencing sodium valproate. Unexpectedly, liver function returned to normal on stopping the drug. Sequencing of the mitochondrial polymerase gamma gene (POLG1) revealed four heterozygous substitutions, two of which have been identified in cases of Alpers-Huttenlocher disease. [ABSTRACT FROM AUTHOR]

We report the case of a 2-year-old boy with seizures who developed hepatic failure shortly after commencing sodium valproate. Unexpectedly, liver function returned to normal on stopping the drug. Sequencing of the mitochondrial polymerase γ gene (POLG1) revealed four heterozygous substitutions, two of which have been identified in cases of Alpers-Huttenlocher disease. [ABSTRACT FROM AUTHOR]

The m.8993T→C MTATP6 mutation of mitochondrial DNA (mtDNA) usually causes mitochondrial disease in childhood, but was recently described in a family with adult onset ataxia and polyneuropathy. Cytochrome c oxidase muscle histochemistry, which is the standard clinical investigation for mitochondrial disease in adults, is usually normal in patients with MTATP6 mutations. This raises the possibility that these cases have been missed in the past. We therefore studied 308 patients with unexplained ataxia and 96 patients with suspected Charcot-Marie-Tooth disease to determine whether the m.8993T→C MTATP6 mutation is common in unexplained inherited ataxia and/or polyneuropathy. We identified a three-generation family with the m.8993T→C mutation of mtDNA. One subject had episodic ataxia (EA) and transient hemipareses, broadening the phenotype. However, no further cases were identified in an additional cohort of 191 patients with suspected EA. In conclusion, m.8993T→C MTATP6 should be considered in patients with unexplained ataxia, CMT or EA, but cases are uncommon. [ABSTRACT FROM AUTHOR]

Aim: To investigate a possible association between mitochondrial haplogroups and primary open angle glaucoma (POAG). Methods: Genomic DNA was extracted from 140 POAG patients and 75 healthy individuals. Restriction enzyme digest analysis of polymerase chain reaction (PCR) amplified fragments was used to determine the mitochondrial haplogroup of each patient and control. Results: The median age was 73 years for the POAG patients (range 51-87, SD 8.01) and 78 years for the controls (range 68-90, SD 4.4). Mean lOP was 20.8 mm Hg for the patients (SD 2.6) and 16.2 mmHg for the controls (SD 3.4). Median cup/disc ratio was 0.8 and 0.3 for patients and controls respectively. No statistically significant difference was found in the haplogroup distribution between the POAG patients and the healthy individuals (Fisher's exact test). Conclusion: In this cohort, mitochondrial haplogroups do not appear to contribute to the pathogenesis of POAG. [ABSTRACT FROM AUTHOR]

Cites a study which found that primary open angle glaucoma (POAG) is associated with a specific p53 gene haplotype that causes blind registration in Great Britain. Major risk factors of POAG; Link of POAG with the genes encoding myocilin and optineurin; Potential role of p53 and apoptosis in POAG.

Presents a letter to the editor about an autosomal dominant syndrome.

A letter to the editor is presented which emphasizes on fragile X syndrome premutation which is presented as essential tremor.

Presents a letter to the editor about aciclovir induced posterior leucoencephalopathy

Presents a letter to the editor in response to the article on 16189C polymorphic sequence variant and late onset dementia.

This article focuses on a study that finds no association of the mitochondrial DNA A 12308G polymorphism with increased risk of stroke in patients with the A3242G mutation. Only 50% of patients carrying the A3243G mutation have stroke-like episodes and the reason for this clinical variability remains poorly understood. It is responsible for 80% of cases of MELAS, mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes, and is also associated with several other phenotypes including maternally inherited diabetes and deafness and chronic progressive external ophthalmoplegia. Researchers carried out a large, multicentre study to investigate the A12308G polymorphism in a group of 107 unrelated family index cases harbouring the A3243G mutation.

Background Genomic copy number variants have been shown to be responsible for multiple genetic diseases. Recently, a duplication in septin 9 (SEPT9) was shown to be causal for hereditary neuralgic amyotrophy (HNA), an episodic peripheral neuropathy with autosomal dominant inheritance. This duplication was identified in 12 pedigrees that all shared a common founder haplotype. Methods and results Based on array comparative genomic hybridisation, we identified six additional heterogeneous tandem SEPT9 duplications in patients with HNA that did not possess the founder haplotype. Five of these novel duplications are intragenic and result in larger transcript and protein products, as demonstrated through reverse transcription-PCR and western blotting. One duplication spans the entire SEPT9 gene and does not generate aberrant transcripts and proteins. The breakpoints of all the duplications are unique and contain regions of microhomology ranging from 2 to 9 bp in size. The duplicated regions contain a conserved 645 bp exon within SEPT9 in which HNA-linked missense mutations have been previously identified, suggesting that the region encoded by this exon is important to the pathogenesis of HNA. Conclusions Together with the previously identified founder duplication, a total of seven heterogeneous SEPT9 duplications have been identified in this study as a causative factor of HNA. These duplications account for one third of the patients in our cohort, suggesting that duplications of various sizes within the SEPT9 gene are a common cause of HNA. [ABSTRACT FROM AUTHOR]

Background: Primary open angle glaucoma is a progressive optic neuropathy characterised by the selective loss of retinal ganglion cells, pathological optic disc cupping and visual field defects. The OPA1 gene encodes an inner mitochondrial membrane protein crucial for normal mitochondrial function, and pathogenic mutations cause autosomal dominant optic atrophy by specifically targeting retinal ganglion cells. This raises the distinct possibility that more subtle genetic variations in OPA1 could alter the risk of developing glaucoma. Methods: 137 patients with primary open angle glaucoma (67 patients with high-tension glaucoma (HTG), 70 patients with normal-tension glaucoma (NTG)) and 75 controls from the North East of England were studied. Three single-nucleotide polymorphisms in intron 8 (IVS8+4c->t and IVS8+32t->c) and exon 4 (c.473A->G) of the OPA1 gene were genotyped in the study group. In addition, the entire OPA1 coding region was sequenced in 24 individuals with the CT/TT compound genotype using standard BigDye chemistries. Results: There was no difference in either allele or genotype frequency for the IVS8+32t->c single-nucleotide polymorphisms between patients and controls, but there was a significant association between the T allele at IVS8+4c->t and the risk of developing NTG (OR=2.04, 95% CI=1.10 to 3.81, p=0.004), but not HTG. Logistic regression analysis also confirmed a strong association between the CT/TT compound genotype at IVS8+4 and IVS8+32 with NTG (OR=29.75, 95% CI=3.83 to 231.21, p=0.001). Conclusions: The CT/TT compound genotype at IVS8+4 and IVS8+32 is a strong genetic risk determinant for NTG but not HTG. [ABSTRACT FROM AUTHOR]

The article focuses on a study which examined the presence of the ferritin light polypeptide gene FTL in French family with a progressive adult onset movement disorder and cystic cavitation of the basal ganglia. Using brain magnetic resonance imaging (MRI), FTL was discovered on the family. In addition, polymerase chain reaction (PCR) analysis of the FTL of one of the French patients showed a banding pattern similar to that seen in affected individuals from a Cumbrian family, leading to the diagnosis of neuroferritinopathy.

An image of the spes casvus is presented.