Idiopathic infertility as a feature of genome instability

Funding Information: The authors are very grateful to habil. med. Jekaterina Erenpreisa for her critical review of the paper. Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland.Genome instability may play a role in severe cases of male infertility, with disrupted spermatogenesis being just one manifestation of decreased general health and increased morbidity. Here, we review the data on the association of male infertility with genetic, epigenetic, and environmental alterations, the causes and consequences, and the methods for assessment of genome instability. Male infertility research has provided evidence that spermatogenic defects are often not limited to testicular dysfunction. An increased incidence of urogenital disorders and several types of cancer, as well as overall reduced health (manifested by decreased life expectancy and increased morbidity) have been reported in infertile men. The pathophysiological link between decreased life expectancy and male infertility supports the notion of male infertility being a systemic rather than an isolated condition. It is driven by the accumulation of DNA strand breaks and premature cellular senescence. We have presented extensive data supporting the notion that genome instability can lead to severe male infertility termed “idiopathic oligo-astheno-teratozoospermia.” We have detailed that genome instability in men with oligo-astheno-teratozoospermia (OAT) might depend on several genetic and epigenetic factors such as chromosomal heterogeneity, aneuploidy, micronucleation, dynamic mutations, RT, PIWI/piRNA regulatory pathway, pathogenic allelic variants in repair system genes, DNA methylation, environmental aspects, and lifestyle factors.Peer reviewe

Alanyl-tRNA synthetase 1 gene variants in hereditary neuropathy genotype and phenotype overview

Funding Information: This research is funded by Latvian Science Council, Project Discovering biomarkers of disease progression and variability in Charcot-Marie-Tooth neuropathy, No lzp-2021/1-0327. Funding Information: The Article Processing Charge was funded by Fundamental and Applied Research Project, lzp-2021/1-0327. Publisher Copyright: Copyright © 2022 The Author(s).Background and Objectives Our objective was to report 2 novel variants and to reclassify previously reported alanyl-tRNA synthetase 1 (AARS1) variants associated with hereditary neuropathy and to summarize the clinical features of a previously published cohort of patients. Methods We performed detailed neurologic and electrophysiologic assessments and segregation analysis of 2 unrelated families with Charcot-Marie-Tooth (CMT) disease with novel variants in the AARS1 gene. Via literature search, we found studies that included neuropathy cases with AARS1 variants; we then reviewed and reclassified these variants. Results We identified 2 CMT families harboring previously unreported likely pathogenic AARS1 variants: c.1823C>A p.(Thr608Lys) and c.1815C>G p.(His605Gln). In addition, we reinterpreted a total of 35 different AARS1 variants reported in cases with neuropathy from the literature: 9 variants fulfilled the current criteria for being (likely) pathogenic. We compiled and summarized standardized clinical and genotypic information for 90 affected individuals from 32 families with (likely) pathogenic AARS1 variants. Most experienced motor weakness and sensory loss in the lower limbs. Discussion In total, 11 AARS1 variants can currently be classified as pathogenic or likely pathogenic and are associated with sensorimotor axonal or intermediate, slowly progressive polyneuropathy with common asymmetry and variable age of symptom onset with no apparent involvement of other organ systems.publishersversionPeer reviewe

Case report : Multiple UGT1A1 gene variants in a patient with Crigler-Najjar syndrome

Publisher Copyright: © 2018 The Author(s).Background: Inherited unconjugated hyperbilirubinemia is caused by variants in the gene UGT1A1 leading to Gilbert's syndrome and Crigler-Najjar syndrome types I and II. These syndromes are differentiated on the basis of UGT1A1 residual enzymatic activity and its affected bilirubin levels and responsiveness to phenobarbital treatment. Case presentation: In this report, we present a boy with Crigler-Najjar syndrome type II with high unconjugated bilirubin levels that decreased after phenobarbital treatment but increased in adolescence. Four different UGT1A1 gene variants have been identified for this patient, of which one is novel (g.11895-11898del) most likely confirming diagnose molecularly. Conclusions: The presented case highlights the challenges encountered with the interpretation of molecular data upon identification of multiple variants in one gene that are causing different degree reducing effect on enzyme activity leading to several clinical conditions.Peer reviewe

Clinical and neurophysiological spectrum of polyneuropathies in children

Peripheral neuropathy is a disorder of the peripheral nerves and results from a disturbance of structure and/or function of the peripheral sensory, motor and/or autonomic neurons. The possible aetiology of peripheral neuropathies is diverse, but inflammatory and hereditary diseases of the peripheral nerves predominate in childhood. The aim of this study was to determine the clinical and electrophysiological profile of large nerve fibre neuropathy detected by nerve conduction studies (NCS) in children over a 10-year period at the Children’s Clinical University Hospital in Latvia. Based on NCS findings, 165 children between 2008 and 2018 were diagnosed with polyneuropathy. In our study, the majority of children had peripheral neuropathy due to acquired causes, mostly due to diabetes mellitus; roughly one in five of the patients had hereditary neuropathy. Almost half of the patients had motor deficits, which were more prevalent in toxic and inflammatory neuropathies. A little less than a third of patients complained of pain as well as presenting with autonomic dysfunction symptoms. The NCS demonstrated a demyelinating neuropathy in 52 cases (31%), an axonal neuropathy in 34 cases (21%), and mixed polyneuropathy in 79 cases (48%). Our study investigated the clinical and electrophysiological characteristics of polyneuropathies diagnosed with NCS in children. Most of the polyneuropathies in our study were hereditary and diabetic neuropathies with combined (myelin and axon) damage to nerve fibres. Almost all clinical symptoms of polyneuropathy were present in all aetiological groups.Peer reviewe

A systematic review and standardized clinical validity assessment of genes involved in female reproductive failure

Genetic testing is becoming increasingly required at almost every stage of failed female reproduction/infertility. Nonetheless, clinical evidence for the majority of identified gene-disease relationships is ill-defined, thus leading to difficult gene variant interpretation and poor translation of existing knowledge into clinics. We aimed to identify the genes that have ever been implicated in monogenic female reproductive failure in humans and to classify the identified gene-disease relationship pairs using a standardized clinical validity assessment. A PubMed search following PRISMA guidelines was conducted on 20 September 2021 aiming to identify studies pertaining to genetic causes of phenotypes of female reproductive failure. The clinical validity of identified gene-disease pairs was assessed using standardized criteria, counting whether sufficient genetic and experimental evidence has been accumulated to consider a single gene 'characterized' for a single Mendelian disease. In total, 1256 articles were selected for the data extraction; 183 unique gene-disease pairs were classified spanning the following phenotypes: hypogonadotropic hypogonadism, ovarian dysgenesis, premature ovarian failure/insufficiency, ovarian hyperstimulation syndrome, empty follicle syndrome, oocyte maturation defect, fertilization failure, early embryonic arrest, recurrent hydatidiform mole, adrenal disfunction and Mullerian aplasia. Twenty-four gene-disease pairs showed definitive evidence, 36 - strong, 19 - moderate, 81 - limited and 23 - showed no evidence. Here, we provide comprehensive, systematic and timely information on the genetic causes of female infertility. Our classification of genetic causes of female reproductive failure will facilitate the composition of up-to-date guidelines on genetic testing in female reproduction, the development of diagnostic gene panels and the advancement of reproductive decision-making.publishersversionPeer reviewe

Genetic Basis of Early Onset Atrial Fibrillation in Patients without Risk Factors

Funding Information: This research was funded by the Latvian Council of Science, project, “The role of clonal hemato-poiesis of indeterminate potential as a potential driver of cardiovascular diseases and its associ-ation with clinical outcome”, project No. lzp-2021/1-0293. Publisher Copyright: © 2023 by the authors.Background: Atrial fibrillation (AF) is the most common arrhythmia and typically occurs in elderly patients with other cardiovascular and extracardiac diseases. However, up to 15% of AF develops without any related risk factors. Recently, the role of genetic factors has been highlighted in this particular form of AF. Aims: The aims of this study were to determine the prevalence of pathogenic variants in early-onset AF in patients without known disease-related risk factors and to identify any structural cardiac abnormalities in these patients. Materials and Methods: We conducted exome sequencing and interpretation in 54 risk factor-free early-onset AF patients and further validated our findings in a similar AF patient cohort from the UK Biobank. Results: Pathogenic/likely pathogenic variants were found in 13/54 (24%) patients. The variants were identified in cardiomyopathy-related and not arrhythmia-related genes. The majority of the identified variants were TTN gene truncating variants (TTNtvs) (9/13 (69%) patients). We also observed two TTNtvs founder variants in the analysed population—c.13696C>T p.(Gln4566Ter) and c.82240C>T p.(Arg27414Ter). Pathogenic/likely pathogenic variants were found in 9/107 (8%) individuals from an independent similar AF patient cohort from the UK Biobank. In correspondence with our Latvian patients, only variants in cardiomyopathy-associated genes were identified. In five (38%) of the thirteen Latvian patients with pathogenic/likely pathogenic variants, dilation of one or both ventricles was identified on a follow-up cardiac magnetic resonance scan. Conclusions: We observed a high prevalence of pathogenic/likely pathogenic variants in cardiomyopathy-associated genes in patients with risk factor-free early-onset AF. Moreover, our follow-up imaging data indicate that these types of patients are at risk of developing ventricular dilation. Furthermore, we identified two TTNtvs founder variants in our Latvian study population.publishersversionPeer reviewe

Health-related quality of life and binge eating among adolescent girls with PCOS

Publisher Copyright: Copyright: © 2022 The Author(s).Background: Polycystic ovary syndrome (PCOS) affects 3–8% of adolescents. It is characterized by hyperandrogenism and oligoovulation/anovulation. PCOS has a negative impact on health-related quality of life (HRQoL). However, the extents to which factors influence total HRQoL of adolescents are not known. Adult PCOS patients have a higher incidence of binge eating than the general reproductive-age female population. Limited data on binge eating in adolescents with PCOS are available. Aim of this study was to investigate how PCOS and its associated factors, including binge eating, affect the HRQoL of adolescent girls. Methods: This case-control study recruited 63 adolescent girls 13–18 years of age with PCOS and 66 age-matched healthy controls. The PCOS health-related quality of life questionnaire (PCOSQ) and Binge Eating Scale (BES) were used. Multiple linear regression was executed to establish exact predictors and their effect on total HRQoL. Results: HRQoL was significantly lower in adolescents with PCOS than controls (4.9 (interquartile range (IQR) 1.5) vs. 5.8 (IQR 0.9) points). The lowest scores were found in the body hair and weight domains. BES results were not significantly higher in the PCOS group than in the control group (p = 0.727). The main predictors for total HRQoL were PCOS diagnosis per se (β = –1.002; p < 0.001), BES score (β = –0.27; p = 0.004) and body mass index (BMI) percentile (β = –0.007; p = 0.013). Conclusions: The lower HRQoL in adolescents with PCOS is attributable to the diagnosis of PCOS, BES score and BMI percentile, confirming the importance of tailoring clinical interventions and counselling to address the domains (i.e., symptoms of hirsutism and weight concerns) causing distress and lowering HRQoL. Further implementation research is required to evaluate the impact of targeted interventions on the HRQoL of adolescent girls with PCOS.publishersversionPeer reviewe

Plasma neurofilament light chain level is not a biomarker of Charcot–Marie–Tooth disease progression: Results of 3-year follow-up study

BACKGROUND AND PURPOSE: Charcot-Marie-Tooth disease (CMT) is a hereditary, slowly progressive neuropathy. Currently, there are no effective pharmacological treatments or sensitive disease activity biomarkers available. The aim of this study was to demonstrate the change in plasma neurofilament light chain (NfL) over time in a CMT cohort and analyse the association between CMT severity and NfL level. METHODS: Initially, 101 CMT patients and 64 controls were enrolled in the study. Repeated evaluation was performed in 73 patients and 28 controls at a 3-year interval. Disease severity assessment included clinical evaluation with CMT Neuropathy Score version 2 (CMTNSv2). Plasma NfL concentration was measured using the Simoa (single molecule array) NfL assay. RESULTS: Plasma NfL concentration was increased in the CMT group compared with controls (p < 0.001). Overall NfL level increased over the 3-year interval in both CMT (p = 0.012) and control (p = 0.001) groups. However, in 22 of 73 CMT patients and seven of 28 controls, the NfL level decreased from the baseline. Analysing the association between 3-year change in plasma NfL and disease severity (CMTNSv2), there was no correlation in the CMT group (r = 0.228, p = 0.052) or different CMT subgroups. CONCLUSIONS: Our study verifies increased plasma NfL concentrations in patients with CMT compared with controls. Longitudinal 3-year data showed a variable change in NfL levels between CMT subtypes. There was no association between change in NfL over time and disease severity. These findings suggests that NfL is not a biomarker for CMT progression

Long-Term Immunological Memory of SARS-CoV-2 Is Present in Patients with Primary Antibody Deficiencies for up to a Year after Vaccination

Funding Information: This research was funded by the Latvian Council of Science project Nr.lzp-2020/1–0269. Publisher Copyright: © 2023 by the authors.Some studies have found increased coronavirus disease-19 (COVID-19)-related morbidity and mortality in patients with primary antibody deficiencies. Immunization against COVID-19 may, therefore, be particularly important in these patients. However, the durability of the immune response remains unclear in such patients. In this study, we evaluated the cellular and humoral response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antigens in a cross-sectional study of 32 patients with primary antibody deficiency (n = 17 with common variable immunodeficiency (CVID) and n = 15 with selective IgA deficiency) and 15 healthy controls. Serological and cellular responses were determined using enzyme-linked immunosorbent assay and interferon-gamma release assays. The subsets of B and T lymphocytes were measured using flow cytometry. Of the 32 patients, 28 had completed the vaccination regimen with a median time after vaccination of 173 days (IQR = 142): 27 patients showed a positive spike-peptide-specific antibody response, and 26 patients showed a positive spike-peptide-specific T-cell response. The median level of antibody response in CVID patients (5.47 ratio (IQR = 4.08)) was lower compared to healthy controls (9.43 ratio (IQR = 2.13)). No difference in anti-spike T-cell response was found between the groups. The results of this study indicate that markers of the sustained SARS-CoV-2 spike-specific immune response are detectable several months after vaccination in patients with primary antibody deficiencies comparable to controls.publishersversionpublishersversionPeer reviewe

GJB1 Gene Analysis in Two Extended Families with X-Linked Charcot-Marie-Tooth Disease

Funding Information: The study was carried out using the internal research grant in Riga Stradins University. Publisher Copyright: © 2021 The Author(s). Published by S. Karger AG, Basel.X-linked Charcot-Marie-Tooth (CMT) disease type I (CMTX1) is the second most frequent type of CMT disease caused by pathogenic variants in the GJB1 gene. We described 2 extended cases (families) with CMTX1 with identified pathogenic variants - p.Val139Met and p.Arg215Trp. In both the families, neurological symptoms started earlier in male than in female patients. In some family members, molecular diagnostics was performed prior to neurological investigation due to family cascade screening. There was variable neurological phenotype representing CMT. Conclusions: There is a large clinical heterogeneity in CMTX, even amongst the family members.publishersversionPeer reviewe