Syndromic Monogenic Diabetes Genes Should be Tested in Patients With a Clinical Suspicion of MODY

This is the author accepted manuscript. The final version is available from the American Diabetes Association via the DOI in this recordThis article contains supplementary material online at https://doi.org/10.2337/figshare.17000605At present, outside of infancy, genetic testing for monogenic diabetes is typically for mutations in MODY genes that predominantly result in isolated diabetes. Monogenic diabetes syndromes are usually only tested when this is supported by specific syndromic clinical features. It is not known how frequently patients with suspected MODY have a mutation in a monogenic syndromic diabetes gene and thus missed by present testing regimes.We performed genetic testing of 27 monogenic diabetes genes (including 18 associated with syndromic diabetes) for 1280 patients with a clinical suspicion of MODY from routine clinical care that were not suspected of having monogenic syndromic diabetes. We confirmed monogenic diabetes in 297 (23%) patients. Mutations in 7 different syndromic diabetes genes accounted for 19% (95%CI 15-24%) of all monogenic diabetes. The mitochondrial m.3243A>G and mutations in HNF1B were responsible for the majority of mutations in syndromic diabetes genes. They were also the 4th and 5th most common causes of monogenic diabetes overall. These patients lacked typical features and their diabetes phenotypes overlapped with non-syndromic monogenic diabetes patients. Syndromic monogenic diabetes genes (particularly m.3243A>G and HNF1B) should be routinely tested in patients with suspected MODY that do not have typical features of a genetic syndrome.Wellcome TrustNational Institute for Health Research (NIHR

Cross-sectional and longitudinal studies suggest pharmacological treatment used in patients with glucokinase mutations does not alter glycaemia

This is a freely-available open access publication. Please cite the published version which is available via the DOI link in this record.Heterozygous glucokinase (GCK) mutations cause mild, fasting hyperglycaemia from birth. Although patients are usually asymptomatic and have glycaemia within target ranges, some are put on pharmacological treatment. We aimed to investigate how many patients are on pharmacological treatment and the impact of treatment on glycaemic control.European Community’s Seventh Framework ProgrammeNIHR Exeter Clinical Research FacilityWellcome Trus

Homozygous Hypomorphic HNF1A Alleles Are a Novel Cause of Young-Onset Diabetes and Result in Sulfonylurea-Sensitive Diabetes

Objective: Heterozygous loss-of-function mutations in HNF1A cause maturity-onset diabetes of the young (MODY). Affected individuals can be treated with low-dose sulfonylureas. Individuals with homozygous HNF1A mutations causing MODY have not been reported. Research design and methods: We phenotyped a kindred with young-onset diabetes and performed molecular genetic testing, a mixed meal tolerance test, a sulfonylurea challenge, and in vitro assays to assess variant protein function. Results: A homozygous HNF1A variant (p.A251T) was identified in three insulin-treated family members diagnosed with diabetes before 20 years of age. Those with the homozygous variant had low hs-CRP levels (0.2-0.8 mg/L), and those tested demonstrated sensitivity to sulfonylurea given at a low dose, completely transitioning off insulin. In silico modeling predicted a variant of unknown significance; however, in vitro studies supported a modest reduction in transactivation potential (79% of that for the wild type; P < 0.05) in the absence of endogenous HNF1A. Conclusions: Homozygous hypomorphic HNF1A variants are a cause of HNF1A-MODY. We thus expand the allelic spectrum of variants in dominant genes causing diabetes.This article is freely available via Open Access. Click on the publisher URL to access it via the publisher's site.This work was undertaken with funds from the Diabetes Research & Wellness Foundation (through a Sutherland-Earl Fellowship 2013–2016) and the Imperial College Healthcare Charity, and with infrastructure support from the National Institute for Health Research (NIHR) Imperial Biomedical Research Centre (BRC), Imperial Clinical Research Facility, and Clinical Research Network. S.M. is currently supported by a Future Leaders Mentorship Award from the European Association for the Study of Diabetes. A.J. was a Diabetes UK George Alberti Clinical Research Fellow when contributing to this study. S.E. received a Senior Investigator Award from Wellcome Trust. A.L.G. is a Wellcome Senior Fellow in Basic Biomedical Science. Part of this work was funded in Oxford by the Wellcome Trust (grants 095101 and 200837 [both to A.L.G.]). The research was also funded by the NIHR Oxford and BRC (to A.L.G.).Accepted version, submitted versio

Penetrance and expressivity of mitochondrial variants in a large clinically unselected population

\ua9 The Author(s) 2023. Published by Oxford University Press. Whole genome sequencing (WGS) from large clinically unselected cohorts provides a unique opportunity to assess the penetrance and expressivity of rare and/or known pathogenic mitochondrial variants in population. Using WGS from 179 862 clinically unselected individuals from the UK Biobank, we performed extensive single and rare variant aggregation association analyses of 15 881 mtDNA variants and 73 known pathogenic variants with 15 mitochondrial disease-relevant phenotypes. We identified 12 homoplasmic and one heteroplasmic variant (m.3243A&gt;G) with genome-wide significant associations in our clinically unselected cohort. Heteroplasmic m.3243A&gt;G (MAF = 0.0002, a known pathogenic variant) was associated with diabetes, deafness and heart failure and 12 homoplasmic variants increased aspartate aminotransferase levels including three low-frequency variants (MAF ~0.002 and beta~0.3 SD). Most pathogenic mitochondrial disease variants (n = 66/74) were rare in the population (&lt;1:9000). Aggregated or single variant analysis of pathogenic variants showed low penetrance in unselected settings for the relevant phenotypes, except m.3243A&gt;G. Multi-system disease risk and penetrance of diabetes, deafness and heart failure greatly increased with m.3243A&gt;G level ≥ 10%. The odds ratio of these traits increased from 5.61, 12.3 and 10.1 to 25.1, 55.0 and 39.5, respectively. Diabetes risk with m.3243A&gt;G was further influenced by type 2 diabetes genetic risk. Our study of mitochondrial variation in a large-unselected population identified novel associations and demonstrated that pathogenic mitochondrial variants have lower penetrance in clinically unselected settings. m.3243A&gt;G was an exception at higher heteroplasmy showing a significant impact on health making it a good candidate for incidental reporting

HNF1B mutations are associated with a Gitelman-like tubulopathy that develops during childhood

Mutations in the transcription factor hepatocyte nuclear factor 1B (HNF1B) are the most common inherited cause of renal malformations, yet also associated with renal tubular dysfunction, most prominently magnesium wasting with hypomagnesemia. The presence of hypomagnesemia has been proposed to help select appropriate patients for genetic testing. Yet, in a large cohort, hypomagnesemia was discriminatory only in adult, but not in pediatric patients. We therefore investigated whether hypomagnesemia and other biochemical changes develop with age.This article is freely available via Open Access. Click on the Additional Link to access full-text

‘Pushing back’: People newly diagnosed with dementia and their experiences of the Covid‐19 pandemic restrictions in England

Background and Objectives Research into people with dementia's experiences of the Covid-19 pandemic has tended to focus on vulnerabilities and negative outcomes, with the risk of reproducing a discourse in which people with dementia are positioned as passive. Informed by concepts positioning people with dementia as ‘active social agents’, we aimed to identify the pandemic-related challenges faced by people recently diagnosed with dementia and examine the ways in which they actively coped with, and adapted to, these challenges. Research Design and Methods In-depth interviews with 21 people recently diagnosed with dementia, recruited through an existing national cohort. Data was analysed thematically using Framework. Findings Key challenges included reduced social contact, loneliness and loss of social routines; difficulties accessing and trusting health services; dementia-unfriendly practices; and disparate experiences of being able to ‘get out’ into the physical neighbourhood. People with dementia responded to challenges by maintaining and extending their social networks and making the most of ‘nodding acquaintances’; learning new skills, for communication and hobbies; supporting others, engaging in reciprocal exchange and valuing connection with peers; seeking help and advocacy and challenging and resisting dementia-unfriendly practices; maintaining and adapting habitual spatial practices and being determined to ‘get out’; and employing similar emotional coping strategies for the pandemic and dementia. Conclusions Support for people with dementia, especially during public health crises when carers and services are under pressure, should involve utilising existing capacities, appropriately supporting the acquisition of new knowledge and skills, ‘safety-netting’ through the availability of a named professional, advocacy and support and use of ‘check-in calls’ and creating supportive social and environmental circumstances for people with dementia to sustain their own well-being

Improved genetic testing for monogenic diabetes using targeted next-generation sequencing

addresses: Institute for Biomedical and Clinical Science, University of Exeter Medical School, Barrack Road, Exeter EX2 5DW, UK. [email protected]: PMCID: PMC3737433types: Journal Article; Research Support, Non-U.S. Gov'tOpen Access ArticleCurrent genetic tests for diagnosing monogenic diabetes rely on selection of the appropriate gene for analysis according to the patient's phenotype. Next-generation sequencing enables the simultaneous analysis of multiple genes in a single test. Our aim was to develop a targeted next-generation sequencing assay to detect mutations in all known MODY and neonatal diabetes genes

Optimising experimental design for MEG resting state functional connectivity measurement

The study of functional connectivity using magnetoencephalography (MEG) is an expanding area of neuroimaging, and adds an extra dimension to the more common assessments made using fMRI. The importance of such metrics is growing, with recent demonstrations of their utility in clinical research, however previous reports suggest that whilst group level resting state connectivity is robust, single session recordings lack repeatability. Such robustness is critical if MEG measures in individual subjects are to prove clinically valuable. In the present paper, we test how practical aspects of experimental design affect the intra-subject repeatability of MEG findings; specifically we assess the effect of co-registration method and data recording duration. We show that the use of a foam head-cast, which is known to improve co-registration accuracy, increased significantly the between session repeatability of both beamformer reconstruction and connectivity estimation. We also show that recording duration is a critical parameter, with large improvements in repeatability apparent when using ten minute, compared to five minute recordings. Further analyses suggest that the origin of this latter effect is not underpinned by technical aspects of source reconstruction, but rather by a genuine effect of brain state; short recordings are simply inefficient at capturing the canonical MEG network in a single subject. Our results provide important insights on experimental design and will prove valuable for future MEG connectivity studies

Type 1 diabetes genetic risk score discriminates between monogenic and Type 1 diabetes in children diagnosed at the age of < 5 years in the Iranian population

This is the final version. Available on open access from Wiley via the DOI in this recordAim To examine the extent to which discriminatory testing using antibodies and Type 1 diabetes genetic risk score, validated in European populations, is applicable in a non‐European population. Methods We recruited 127 unrelated children with diabetes diagnosed between 9 months and 5 years from two centres in Iran. All children underwent targeted next‐generation sequencing of 35 monogenic diabetes genes. We measured three islet autoantibodies (islet antigen 2, glutamic acid decarboxylase and zinc transporter 8) and generated a Type 1 diabetes genetic risk score in all children. Results We identified six children with monogenic diabetes, including four novel mutations: homozygous mutations in WFS1 (n=3), SLC19A2 and SLC29A3, and a heterozygous mutation in GCK. All clinical features were similar in children with monogenic diabetes (n=6) and in the rest of the cohort (n=121). The Type 1 diabetes genetic risk score discriminated children with monogenic from Type 1 diabetes [area under the receiver‐operating characteristic curve 0.90 (95% CI 0.83–0.97)]. All children with monogenic diabetes were autoantibody‐negative. In children with no mutation, 59 were positive to glutamic acid decarboxylase, 39 to islet antigen 2 and 31 to zinc transporter 8. Measuring zinc transporter 8 increased the number of autoantibody‐positive individuals by eight. Conclusions The present study provides the first evidence that Type 1 diabetes genetic risk score can be used to distinguish monogenic from Type 1 diabetes in an Iranian population with a large number of consanguineous unions. This test can be used to identify children with a higher probability of having monogenic diabetes who could then undergo genetic testing. Identification of these individuals would reduce the cost of treatment and improve the management of their clinical course.Wellcome TrustDiabetes U

Using digital technologies to facilitate social inclusion during the COVID-19 pandemic: Experiences of co-resident and non-co-resident family carers of people with dementia from DETERMIND-C19

Background The COVID-19 pandemic triggered rapid and unprecedented changes in the use of digital technologies to support people's social inclusion. We examined whether and how co-resident and non-co-resident family carers of people with dementia engaged with digital technologies during this period. Methods Throughout November 2020-February 2021, we interviewed 42 family carers of people with dementia from our DETERMIND-C19 cohort. Preliminary analysis was conducted through Framework analysis, followed by an inductive thematic analysis. Findings Digital technologies served as a Facilitator for social inclusion by enabling carers to counter the effects of the differing restrictions imposed on them so they could remain socially connected and form a sense of solidarity, access resources and information, engage in social and cultural activities and provide support and independence in their caring role. However, these experiences were not universal as carers discussed some Challenges for tech inclusion, which included preferences for face-to-face contact, lack of technological literacy and issues associated with the accessibility of the technology. Conclusion Many of the carers engaged with Information and Communication Technologies, and to a lesser extent Assistive Technologies, during the pandemic. Whilst carers experienced different challenges due to where they lived, broadly the use of these devices helped them realise important facets of social inclusion as well as facilitated the support they provided to the person with dementia. However, to reduce the ‘digital divide’ and support the social inclusion of all dementia carers, our findings suggest it is essential that services are attuned to their preferences, needs and technological abilities