Genetic Causes Research Articles

O-136 A comprehensive evaluation of spermatogenesis-related genes identifies novel common and rare risk loci for idiopathic severe spermatogenic failure

Abstract Study question Can genome-wide genotyping data be analysed in a hypothesis-driven fashion to better understand the genetic component of male infertility due to severe spermatogenic failure (SPGF)? Summary answer We revealed that both common and rare genetic variants in genomic regions involved in spermatogenesis contribute to the development of idiopathic SPGF. What is known already Spermatogenesis is a tightly regulated process involving the controlled expression of over 2,000 genes. Mutations in spermatogenesis-related genes have been associated with SPGF development. Next-generation sequencing methods are useful for identifying rare mutations that explain monogenic forms of this condition. Additionally, genome-wide association studies (GWAS) have provided valuable insights into the role of common polymorphisms in complex forms of SPGF. Interestingly, novel methods have shown that GWAS datasets can be used to infer rare coding variants that are causal for male infertility phenotypes, but this approach has never been applied to characterise the genetic component of a whole case-control cohort. Study design, size, duration We conducted a thorough examination of both common (minor allele frequency, MAF > 0.01) and rare (MAF < 0.01) genetic variation within a set of 1,797 spermatogenesis genes. This gene panel was meticulously curated through an exhaustive search in the literature and in different databases of male infertility genetics. The genotype data were obtained from a previously published GWAS in Europeans, encompassing over 6 million polymorphisms. Participants/materials, setting, methods We analysed a cohort that included 1,274 SPGF patients and 1,951 unaffected controls with European ancestry. Three independent approaches were follow: (1) variant-wise analysis using logistic regression models followed by a meta-analysis of the study cohorts; (2) gene-wise analysis using a Combined Multivariate and Collapsing (CMC) burden test; and (3) identification and characterisation of highly damaging rare coding variants in homozygosity. Multiple testing correction was applied to determine statistical significance Main results and the role of chance Our results suggested a potential association between SPGF and the rs12347237*T variant of the SHOC1 gene in the GWAS population (P = 3.17E-05, OR = 2.94). This association was subsequently validated in an independent Iberian cohort (Pcombined = 6.992E-06, OR = 2.61). Furthermore, our gene-wise analysis showed putative associations through the cumulative effect of some rare and low-frequency variants in SHOC1 (P = 4.9E-03), PCSK4 (P = 1E-04), AP3B1 (P = 5E-04), and DLK1 (P = 5E-04). Remarkably, the rare and common variants identified in SHOC1 are part of the same haplotype block, impacting both coding and non-coding regions. Additionally, we identified 35 individuals carrying 32 very rare and potentially pathogenic variants in homozygosity within the coding regions of the selected genes. Limitations, reasons for caution The analysis of low-frequency variants presents challenges in achieving sufficient statistical power to detect genetic associations. Consequently, independent studies involving large sample sets are essential to replicate our findings. In addition, the specific role of the identified variants in the pathogenic mechanisms of SPGF should be assessed using functional experiments. Wider implications of the findings The discovery of novel genetic risk factors for SPGF and the elucidation of the genetic causes underlying both monogenic and complex forms of SPGF provide new perspectives for personalized medicine and reproductive counselling. Trial registration number not applicable

P-522 Impact of TGFß/BMP/SMAD Pathway on Premature Ovarian Insuffiency (POI)

Abstract Study question Is TGFß/BMP/SMAD pathway altered in women with POI and can results be detected from peripheral blood samples? Summary answer The TGFß/BMP/SMAD pathway mRNA-expression-alterations are detectable in leukocytes of women with Premature Ovarian Insufficiency (POI) paving the way to use it as predictive tool. What is known already A proper ovarian function relies on a complex system of signalling molecules including several BMP/TGFß-superfamily-members expressed in the ovary at different stages of folliculogenesis acting via two types of Serine/Threonine Kinase receptors. The downstream located SMAD proteins are classified into three subclasses according to their function as activated R-SMADs1,2,3,4,9, common-partner SMAD4 or inhibitory SMADs6,7. Mutations in BMPR2 and its ligands have been shown to be related to POI. Recently neurologic studies demonstrated that FMRP(Fragile-X-Mental-Retardation-1-Protein) represses BMPR2 and its gene FMR1(Fragile X Mental-Retardation-1) is one major regulator of follicular development and the most frequent genetic cause of POI if premutated. Study design, size, duration RT-q-PCR was performed to measure the mRNA-levels of SMAD 1,3,4,5, BMPR2 and FMR1. cDNA was synthesized using RNA obtained from leucocytes of patients with POI and of the control group with a normal ovarian reserve. 163 patients diagnosed with POI and 51 women in the control group were recruited between 2008 and 2022 at Heidelberg University’s Women’s Hospital. Participants/materials, setting, methods Blood samples were drawn from every participant to extract leucocyte-RNA and synthesize non-specific cDNA. RT-q-PCR was performed with TaqMan reagents to quantify relative mRNA-expression levels of SMAD 1,3,4, 5, BMPR2 and FMR1. Statistical analysis was performed with Microsoft Excel and GraphPad Prism 10 using the 2–ΔΔCt method and Mann-Whitney-Test. Statistical significance was set to p = 0.05. Main results and the role of chance In our investigation, we observed a consistent and statistically significant decrease in the expression levels of all tested SMADs—SMAD1, SMAD3, SMAD4, and SMAD5—in leukocytes of women diagnosed with POI compared to unaffected controls. The p-values amounted to p < 0.0001 for SMAD1, p = 0.0340 for SMAD3, p < 0.0001 for SMAD4, and p = 0.0076 for SMAD5. However, we did not identify notable differences in the expression levels of FMR1 and BMPR2 between the two groups. These results suggest an alteration in the regulation of the activated downstream elements SMAD 1, 3, and 5 and their common partner SMAD4 in women with POI, emphasizing its potential role as a contributing factor to diminished ovarian function. These effects seem to be independent of BMPR2 and FMR1 and regulated by other receptors and or ligands. Limitations, reasons for caution Our data are limited to mRNA-levels. So further experiments including protein-level and their phosphorylation-status are needed to receive an overall assessment of its impact on ovarian damage. It’s worth noting that the study is concentrated on leukocytes as potential diagnostic tool and results should be cross-checked in ovarian-tissue and cells. Wider implications of the findings The identified alteration in TGFß/BMP/SMAD pathway gene expression in women with POI suggest a role in ovarian damage. Lower expression levels in the aforementioned mRNAs could serve as a potential predictive biomarker for POI risks and putatively used in consultations of women prior to fertility treatment and/or preservation. Trial registration number not applicable

P-352 Investigating the association between DMPK CTG repeats and female hypogonadism in patients affected by Type 1 Myotonic Dystrophy

Abstract Study question Is DPKM CTG repeat size correlated with hypogonadism in female patients affected by type 1 Myotonic Dystrophy? Summary answer The size of CTG repeats in DPKM gene seems to be correlated with hypogonadism severity in female patients affected by type 1 Myotonic Dystrophy. What is known already Type 1 Myotonic Dystrophy (DMT1) is an autosomal dominant degenerative genetic disorder caused by CTG repeats in a single copy of DMPK gene. It is characterized by a broad phenotypic spectrum and a progressive course, involving primarily the muscular and endocrine systems. While DMT1 is a very well-known cause of male hypogonadism, the relationship between DMPK CTG repeats and female hypogonadism is almost unexplored yet. Study design, size, duration We performed a cross–sectional risk study in a cohort of 60 women, with a mean age of 31.5 years (18 to 45 years), referred to our Medical Genetics service for either suspected DMT1 or hypogonadism. The study duration was one year (from November 2022 to November 2023). Participants/materials, setting, methods We performed a DMPK–CTG analysis to investigate a possible correlation between CTG and hypogonadism. Based on the analysis, 11 women were diagnosed with DMT1 with associated hypogonadism, 11 with DMT1 without hypogonadism, 22 did not show DMPK expansion but were affected by hypogonadism, while the remaining 16 showed neither DMPK expansion nor hypogonadism. The patients affected by DMT1 performed standard karyotyping, FRAXA and FRAXE genetic testing to exclude alternative genetic causes of premature ovarian failure. Main results and the role of chance Our results, are indicative that the severity of hypogonadism in DMT1 patients may correlate with the size of CTG repeats. DMPK CTG repeats ranging from 150 – 1000 (range E2) were associated with milder forms of hypogonadism, while the patients having DMPK expansions within the E3 range (1000 CTG repeats or more) showed hypergonadotropic hypogonadism with both infertility and failure of medically assisted reproduction. Limitations, reasons for caution The female patients showing neither DMPK expansion nor hypogonadism did not perform other genetic analysis except DMPK-CTG testing. Moreover, due to the low sample size, our results did not reach statistical significance for a definitive conclusion. Wider implications of the findings To the best of our knowledge, this is the first study to show a possible correlation between female hypogonadism and DMPK CTG repeat size in female patients with type 1 myotonic dystrophy. These results, although preliminary, represent a first step in understanding a hitherto misrecognized clinical consequence of the disease. Trial registration number Not applicable

O-315 Familial endocrine disease increases the risk of pregnancy loss and recurrent pregnancy loss– a nationwide register-based study of 366,548 Danish women

Abstract Study question Is endocrine disease and pregnancy loss associated, and can the association be due to inherited genetic causes? Summary answer Endocrine disease is associated with an increasing number of pregnancy losses. Endocrine disease in parents and siblings increases a woman’s risk of pregnancy loss. What is known already One in four pregnancies results in a pregnancy loss, but only 60% hereof are due to detectable chromosome abnormalities. The remaining 40% are suspected to be caused by other factors such as maternal comorbidity. Recurrent pregnancy loss (RPL) is defined as 2 or 3 consecutive losses and affects 1-3% of couples trying to conceive. Pregnancy loss has been associated with endocrine diseases, e.g., thyroid disease, diabetes, or PCOS. Furthermore, thyroid autoimmunity has been associated with RPL. It is unknown if other endocrine diseases are associated with RPL. To date, there is no evidence for a genetic basis of the risk. Study design, size, duration Danish nationwide cohort study including data from the Danish National Health Registers on ICD-8/ICD-10 diagnosis codes, all pregnancy outcomes and redeemed medicine prescriptions. Endocrine disease was defined as any endocrine disease (e.g., diabetes, thyroid disease, PCOS etc.). The study included in total 366,548 women, including 54,394 women with endocrine disease and 312,154 without endocrine diseases. The study included data from 1973 to 2022. Linkage to parent and siblings was available through the Multi-Generation Registry Lite. Participants/materials, setting, methods The cohort consisted of women born between 1977-1993 with ≥1 pregnancy. The exposure was endocrine disease. Logistic regression models adjusted for birth year provided odds ratios (ORs) for endocrine diseases according to number of pregnancy losses. Parent-offspring and sibling regression provided estimates for familial aggregation, assessing the degree of resemblance between relatives to infer the potential influence of shared familial factors. The variance-covariance matrix was adjusted using the Huber-White method to account for familial clustering. Main results and the role of chance We found a significant association between endocrine disease and pregnancy loss increasing with the number of pregnancy losses; OR and 95%CI for one loss 1.15 (1.12-1.17), two losses 1.31 (1.24-1.38) and ≥ three losses 1.81 (1.70-1.93). Further, endocrine disease was associated with RPL (OR 1.87, (1.74-2.00)). The association was strongest with primary RPL (OR 2.13 (1.94-2.35)), compared to secondary RPL (OR 1.58 (1.42-1.76)). In cases where either of a woman’s parents was diagnosed with an endocrine disease, she also had a higher risk of pregnancy loss (OR 1.06 (1.04–1.08)) and RPL (OR 1.07 (1.01–1.14)), compared to a woman with parents without endocrine disease. If a woman’s sibling had an endocrine disease, the OR for pregnancy loss was 1.07 (1.03–1.11) and RPL 1.17 (1.03–1.33). Further stratification into individual endocrine phenotypes revealed that type 2 diabetes conferred a comparable risk: for offspring of parents with this condition, the risk of pregnancy loss increased to an OR of 1.08 (1.06–1.11), and for siblings, the OR was 1.13 (1.02–1.25). This effect persisted even when adjusting for the disease in the individual experiencing the loss. Limitations, reasons for caution Very early pregnancy losses are often not handled at the hospital and therefore not part of the Danish registers. Thus, there is a risk of underdiagnosed pregnancy losses, although this would be the case for both the exposed and control cohort. Wider implications of the findings Women with RPL should be investigated for endocrine disease, and family history of endocrine disease is an important and novel risk factor that should guide the diagnostic work-up. Identifying the shared mechanism or pleiotropic effects between pregnancy loss and endocrine disease should be a focus area. Trial registration number Research related to this project was supported by the Novo Nordisk Foundation (ID: NNF22OC0077221, NNF23OC0087269) and the William Demant Foundation (salary for Pia Egerup).

Differential physical interactions of wild-type and S59L mutant CHCHD10 with mitochondrial proteases

Background CHCHD10 is a small mitochondrial protein with a C-terminal coiled-coil-helix–coiled-coil-helix domain. The N-terminal region of CHCHD10 is mostly intrinsically disordered. Therefore, CHCHD10 has no catalytic activity other than protein-protein interactions through the CHCH domain or intrinsically disordered region. The S59L mutation in CHCHD10 has been identified as a genetic cause of amyotrophic lateral sclerosis and frontotemporal dementia. However, the disease-causing mechanisms of CHCHD10S59L are not yet fully understood. Our previous study showed that CHCHD10S59L induces PINK1 and Parkin accumulation. PINK1 stabilization in the mitochondria is dependent on proteolytic processing by mitochondrial proteases. It has also been reported that mutant CHCHD10 disrupts protein homeostasis within mitochondria. Therefore, we hypothesized that CHCHD10S59L physically interacts with mitochondrial proteases during the disease pathogenesis. Methods To test this hypothesis, we performed co-immunoprecipitation using transiently transfected wild-type and mutant S59L CHCHD10 in HeLa cells. We employed a dithiobis (succinimidyl propionate) cross-linker to detect transient physical interactions. Results We expected that CHCHD10S59L may activate mitochondrial protease processing or expression and that it interacts with more diverse mitochondrial proteases than the wild type. In general, however, there was no difference in the expression and processing levels of mitochondrial proteases and the proteases that interact with wild-type and CHCHD10S59L. LonP1 degrading unfolded proteins in the mitochondrial matrix was the major proteases that can bind to wild-type CHCHD10 and CHCHD10S59L. LonP1 and HtrA2 were significantly less strongly bound to CHCHD10S59L. Conclusions This result can be interpreted in many different ways, including the regulatory role of CHCHD10 in mitochondrial proteases. However, more precise biochemical and cell biological investigations are required to determine the role of CHCHD10 in the activity of mitochondrial proteases, mechanism of PINK1 stabilization, and disruption of mitochondrial proteostasis.

Identification of a pathogenic mutation in ARPP21 in patients with amyotrophic lateral sclerosis

Background and objectiveBetween 5% and 10% of amyotrophic lateral sclerosis (ALS) cases have a family history of the disease, 30% of which do not have an identifiable underlying genetic cause...

Quantitative Trait Mapping for Zebra-stem in Tomato Confirms a Genetic Cause Involving the Interaction of Unlinked Loci

Zebra-stem of tomato is a disorder characterized by leaf necrosis, wilting, and a stripped pattern on stems of mature plants. Wilting, necrosis, and death of seedlings are also observed. The physiological and genetic causes of zebra-stem are poorly characterized. Anecdotal evidence has suggested pedigrees with S. pimpinellifolium and bacterial speck resistance in the genetic background are often prone to this disorder. We demonstrate a genetic cause using composite interval mapping and association analysis approaches to define quantitative trait loci (QTLs) that contribute to the disorder. A biparental population of F4 partially inbred families was developed for the initial analysis, and four subsequent backcross or F2 populations were used for subsequent validation. Significant QTLs on chromosomes 5 and 10 were identified, explaining ∼60% and 40% of the variation, respectively. Polymorphisms in the Pto locus are strongly associated with the QTL on chromosome 5. The two loci were derived from different parentage, and a significant interaction effect was demonstrated, resulting in the characteristic zebra-stem symptoms when combined.

A 21-Years-Old Man with Mesial Temporal Lobe Epilepsy and Dystonia: A Rare Case Report

Background: Mesial temporal lobe epilepsy (MTLE) with dystonia is a rare case. Seizures and movement disorders have almost the same phenomenology, so it is often difficult to distinguish them. In this study, we report a unique case of MTLE and co-occurring dystonia. Case: A 21 years old male with complaints of seizures since 4 years ago. Seizures of one body jerking and drooling with a duration of less than 5 minutes. Prior to the seizure the patient was nauseous then vomited and followed by an empty mind, after the seizure the patient was confused. The patient also complained of unconscious movements in his right hand since 8 years ago. The movements disappeared when the patient slept. Physical examination revealed dystonic movement with a sensory trick on the right hand. Magnetic resonance imaging (MRI) of the brain with contrast showed bilateral hippocampal atrophy accompanied by left hippocampal sclerosis. Blood laboratory results, electroencephalography, and neurobehavior examination were within normal limits.. Discussion: MTLE can be caused by mutations in SCN1A, VPS13A, C90RF72, or TDP 43. Dystonia can be caused by mutations in SCN1A, TUBB4A, TOR1A, THAP1, or GNAL. SCN1A causes an increase in sodium influx, causing depolarization which causes clinical manifestations in the form of seizures and dystonia. For some disorders, although genetic causes have been identified, the molecular pathophysiology remains largely unknown, requiring further research. Conclusion: For some disorders, although genetic causes have been identified, the molecular pathophysiology remains largely unknown, requiring further research.

Genotype-histotype-phenotype correlations in hyperinsulinemic hypoglycemia.

Hyperinsulinemic hypoglycemia (HH) of pancreatic origin includes congenital hyperinsulinism (CHI), insulinoma, insulinomatosis, and adult-onset non-insulinoma persistent hyperinsulinemic hypoglycemia syndrome (NI-PHHS). In this review, we describe the genotype-histotype-phenotype correlations in HH and their therapeutic implications. CHI can occur from birth or later on in life. Histologically, diffuse CHI shows diffuse beta cell hypertrophy with a few giant nuclei per islet of Langerhans, most frequently caused by loss-of-function mutations in ABCC8 or KCNJ11. Focal CHI is histologically characterized by focal adenomatous hyperplasia consisting of confluent hyperplastic islets, caused by a paternal ABCC8/KCNJ11 mutation combined with paternal uniparental disomy of 11p15. CHI in Beckwith-Wiedemann syndrome is caused by mosaic changes in the imprinting region 11p15.4-11p15.5, leading to segmental or diffuse overgrowth of endocrine tissue in the pancreas. Morphological mosaicism of pancreatic islets is characterized by occurence of hyperplastic (type 1) islets in one or a few lobules and small (type 2) islets in the entire pancreas. Other rare genetic causes of CHI show less characteristic or unspecific histology. HH with a predominant adult onset includes insulinomas, which are pancreatic insulin-producing endocrine neoplasms, in some cases with metastatic potential. Insulinomas occur sporadically or as part of multiple endocrine neoplasia type 1 due to MEN1 mutations. MAFA mutations may histologically lead to insulinomatosis with insulin-producing neuroendocrine microadenomas or neuroendocrine neoplasms. NI-PHHS is mainly seen in adults and shows slight histological changes in some patients, which have been defined as major and minor criteria. The genetic cause is unknown in most cases. The diagnosis of HH, as defined by genetic, histological, and phenotypic features, has important implications for patient management and outcome.

Integration of validated functional evidence to support the pathogenicity of KCNH2 variants

Functional investigation of genetic variants found in long QT syndrome can provide evidence that is needed to confirm the genetic diagnosis and establish the cause of the condition. We performed functional assessment to determine the z-score, using a clinically calibrated automated patch clamp assay, for 2 missense KCNH2 variants found in 2 families that have been diagnosed with long QT syndrome. These variants are currently classified as variant of uncertain significance in ClinVar. The z-scores for homozygous and heterozygous NM_000238.4:c.1819A>T p.(Ile607Phe) from family 1 were –5.16 and –3.97, respectively, and for heterozygous NM_000238.4:c.1832A>G p.(Tyr611Cys) from family 2 was –6.63. The z-scores for these variants are consistent with severe loss-of-function phenotypes. We have established the genetic cause of the long QT syndrome in these 2 families by providing validated functional evidence that supports the pathogenicity of p.(Ile607Phe) and p.(Tyr611Cys). Clinical diagnosis of long QT syndrome has been very successful in providing adequate clinical management for patients. However, functional assessment of variants found in these patients by using variant-specific z-scores can further enhance the current clinical management of patients with long QT syndrome through shared decision making based on validated experimental evidence.

The potential and translational application of infant genetic research.

In the current genomic revolution, the infancy life stage is the most neglected. Although clinical genetics recognizes the value of early identification in infancy of rare genetic causes of disorders and delay, common genetic variation is almost completely ignored in research on infant behavioral and neurodevelopmental traits. In this Perspective, we argue for a much-needed surge in research on common genetic variation influencing infant neurodevelopment and behavior, findings that would be relevant for all children. We now see convincing evidence from different research designs to suggest that developmental milestones, skills and behaviors of infants are heritable and thus are suitable candidates for gene-discovery research. We highlight the resources available to the field, including genotyped infant cohorts, and we outline, with recommendations, special considerations needed for infant data. Therefore, infant genetic research has the potential to impact basic science and to affect educational policy, public health and clinical practice.

FBLN2 is associated with Goldenhar syndrome and is essential for cranial neural crest cell development.

Goldenhar syndrome, a rare craniofacial malformation, is characterized by developmental anomalies in the first and second pharyngeal arches. Its etiology is considered to be heterogenous, including both genetic and environmental factors that remain largely unknown. To further elucidate the genetic cause in a five-generation Goldenhar syndrome pedigree and exploit the whole-exome sequencing (WES) data of this pedigree, we generated collapsed haplotype pattern markers based on WES and employed rare variant nonparametric linkage analysis. FBLN2 was identified as a candidate gene via analysis of WES data across the significant linkage region. A fbln2 knockout zebrafish line was established by CRISPR/Cas9 to examine the gene's role in craniofacial cartilage development. fbln2 was expressed specifically in the mandible during the zebrafish early development, while fbln2 knockout zebrafish exhibited craniofacial malformations with abnormal chondrocyte morphologies. Functional studies revealed that fbln2 knockout caused abnormal chondrogenic differentiation, apoptosis, and proliferation of cranial neural crest cells (CNCCs), and downregulated the bone morphogenic protein (BMP) signaling pathway in the zebrafish model. This study demonstrates the role of FBLN2 in CNCC development and BMP pathway regulation, and highlights FBLN2 as a candidate gene for Goldenhar syndrome, which may have implications for the selection of potential screening targets and the development of treatments for conditions like microtia-atresia.

A novel FAM83G variant from palmoplantar keratoderma patient disrupts WNT signalling via loss of FAM83G-CK1α interaction.

Palmoplantar keratoderma (PPK) is a multi-faceted skin disorder characterized by the thickening of the epidermis and abrasions on the palms and soles of the feet. Among the genetic causes, biallelic pathogenic variants in the FAM83G gene have been associated with PPK in dogs and humans. Here, a novel homozygous variant (c.794G>C, p.Arg265Pro) in the FAM83G gene, identified by whole exome sequencing in a 60-year-old female patient with PPK, is reported. The patient exhibited alterations in the skin of both hands and feet, dystrophic nails, thin, curly and sparse hair, long upper eyelid eyelashes, and poor dental enamel. FAM83G activates WNT signalling through association with ser/thr protein kinase CK1α. When expressed in FAM83G-/- DLD1 colorectal cancer cells, the FAM83GR265P variant displayed poor stability, a loss of interaction with CK1α and attenuated WNT signalling response. These defects persisted in skin fibroblast cells derived from the patient. Our findings imply that the loss of FAM83G-CK1α interaction and subsequent attenuation of WNT signalling underlie the pathogenesis of PPK caused by the FAM83GR265P variant.

Testing the evolutionary potential of an alpine plant: phenotypic plasticity in response to growth temperature outweighs parental environmental effects and other genetic causes of variation.

Phenotypic plasticity and rapid evolution are fundamental processes by which organisms can maintain their function and fitness in the face of environmental changes. Here we quantified the plasticity and evolutionary potential of an alpine herb Wahlenbergia ceracea. Utilizing its mixed-mating system, we generated outcrossed and self-pollinated families that were grown in either cool or warm environments, and that had parents that had also been grown in either cool or warm environments. We then analysed the contribution of environmental and genetic factors to variation in a range of phenotypic traits including phenology, leaf mass per area, photosynthetic function, thermal tolerance, and reproductive fitness. The strongest effect was that of current growth temperature, indicating strong phenotypic plasticity. All traits except thermal tolerance were plastic, whereby warm-grown plants flowered earlier, grew larger, and produced more reproductive stems compared with cool-grown plants. Flowering onset and biomass were heritable and under selection, with early flowering and larger plants having higher relative fitness. There was little evidence for transgenerational plasticity, maternal effects, or genotype×environment interactions. Inbreeding delayed flowering and reduced reproductive fitness and biomass. Overall, we found that W. ceracea has the capacity to respond rapidly to climate warming via plasticity, and the potential for evolutionary change.

Strategic Implementation of Fragile X Carrier Screening in China: A Focused Pilot Study

Fragile X syndrome (FXS) is the leading genetic cause of intellectual disability and autism spectrum disorders. Female premutation carriers exhibit no obvious symptoms during reproductive age, but the premutation allele can expand to full mutation when transmitted to the fetus.. Given the relatively low prevalence but large population, the distinct healthcare system, the middle-income economic status, and low awareness among public and medical professionals, the optimal genetic screening strategy remains unknown. We conducted a pilot study of Fragile X carrier screening in China, involving 22,245 pregnant women and women with childbearing intentions, divided into control and pilot groups. The prevalence of Fragile X carriers in the control group was 1/850, similar to East Asian populations. Strikingly, the prevalence of Fragile X carriers in the pilot group was 1/356, which can be attributed to extensive medical training, participant education, and rigorous genetic counseling and testing protocols. Cost-effectiveness analyses of four strategies—no screening, population-based screening, targeted screening, and our pilot screening—indicated that our pilot screening was the most cost-effective option. A follow-up survey revealed that 55% of respondents reported undergoing screening due to their family history. We have successfully established a standardized system, addressing the challenges of low prevalence, limited awareness, and genetic testing complexities. Our study provides practical recommendations for implementing Fragile X carrier screening in China.

REALM-DCM: A Phase 3, Multinational, Randomized, Placebo-Controlled Trial of ARRY-371797 in Patients With Symptomatic LMNA-Related Dilated Cardiomyopathy.

LMNA (lamin A/C)-related dilated cardiomyopathy is a rare genetic cause of heart failure. In a phase 2 trial and long-term extension, the selective p38α MAPK (mitogen-activated protein kinase) inhibitor, ARRY-371797 (PF-07265803), was associated with an improved 6-minute walk test at 12 weeks, which was preserved over 144 weeks. REALM-DCM (NCT03439514) was a phase 3, randomized, double-blind, placebo-controlled trial in patients with symptomatic LMNA-related dilated cardiomyopathy. Patients with confirmed LMNA variants, New York Heart Association class II/III symptoms, left ventricular ejection fraction ≤50%, implanted cardioverter-defibrillator, and reduced 6-minute walk test distance were randomized to ARRY-371797 400 mg twice daily or placebo. The primary outcome was a change from baseline at week 24 in the 6-minute walk test distance using stratified Hodges-Lehmann estimation and the van Elteren test. Secondary outcomes using similar methodology included change from baseline at week 24 in the Kansas City Cardiomyopathy Questionnaire-physical limitation and total symptom scores, and NT-proBNP (N-terminal pro-B-type natriuretic peptide) concentration. Time to a composite outcome of worsening heart failure or all-cause mortality and overall survival were evaluated using Kaplan-Meier and Cox proportional hazards analyses. REALM-DCM was terminated after a planned interim analysis suggested futility. Between April 2018 and October 2022, 77 patients (aged 23-72 years) received ARRY-371797 (n=40) or placebo (n=37). No significant differences (P>0.05) between groups were observed in the change from baseline at week 24 for all outcomes: 6-minute walk test distance (median difference, 4.9 m [95% CI, -24.2 to 34.1]; P=0.82); Kansas City Cardiomyopathy Questionnaire-physical limitation score (2.4 [95% CI, -6.4 to 11.2]; P=0.54); Kansas City Cardiomyopathy Questionnaire-total symptom score (5.3 [95% CI, -4.3 to 14.9]; P=0.48); and NT-proBNP concentration (-339.4 pg/mL [95% CI, -1131.6 to 452.7]; P=0.17). The composite outcome of worsening heart failure or all-cause mortality (hazard ratio, 0.43 [95% CI, 0.11-1.74]; P=0.23) and overall survival (hazard ratio, 1.19 [95% CI, 0.23-6.02]; P=0.84) were similar between groups. No new safety findings were observed. Findings from REALM-DCM demonstrated futility without safety concerns. An unmet treatment need remains among patients with LMNA-related dilated cardiomyopathy. URL: https://classic.clinicaltrials.gov; Unique Identifiers: NCT03439514, NCT02057341, and NCT02351856.

Genetic Characterization of Kidney Failure of Unknown Etiology in Spain: Findings From the GENSEN Study

Chronic kidney disease (CKD) of unknown etiology (CKDUE) is one of the main global causes of kidney failure. While genetic studies may identify an etiology in these patients, few studies have implemented genetic testing of CKDUE in population-based series of patients which was the focus of the GENSEN. Case series. 818 patients aged ≤45 years at 51 Spanish centers with CKDUE, and either an estimated GFR <15 mL/min/1.73 m2 or treatment with maintenance dialysis or transplantation. Genetic testing for 529 genes associated to inherited nephropathies using high-throughput sequencing (HTS). Pathogenic and/or likely pathogenic (P/LP) gene variants concordant with the inheritance pattern were detected in 203 (24.8%) patients. Variants in type IV collagen genes were the most frequent (COL4A5, COL4A4, COL4A3; 35% of total gene variants), followed by NPHP1, PAX2, UMOD, MUC1 and INF2 (7.3%, 5.9%, 2.5%, 2.5% and 2.5% respectively). Overall, 87 novel variants classified as P/LP were identified. The top 5 most common previously undiagnosed diseases were Alport syndrome spectrum (35% of total positive reports), genetic podocytopathies (19%), nephronophthisis (11%), autosomal dominant tubulointerstitial kidney disease (7%) and congenital anomalies of the kidney and urinary tract (CAKUT: 5%). Family history of kidney disease was reported by 191 (23.3 %) participants and by 65/203 (32.0%) patients with P/LP variants. Missing data. Selection bias resulting from voluntary enrollment. Genomic testing with HTS identified a genetic cause of kidney disease in approximately one quarter of young patients with CKDUE and advanced kidney disease. These findings suggest that genetic studies are a potentially useful tool for the evaluation of people with CKDUE.

Protein and mRNA Expression in Uveal Melanoma Cell Lines Are Related to GNA and BAP1 Mutation Status.

Cell lines are being used in preclinical uveal melanoma (UM) research. Because not all cell lines harbor typical GNAQ or GNA11 hotspot mutations, we aimed at better classifying them and determining whether we could find genetic causes to explain the protein and mRNA expression profiles of the cell lines. We studied protein and mRNA expression of 14 UM cell lines and determined the presence of single nucleotide variants and small insertions and deletions with next-generation sequencing and copy number alterations with a single nucleotide polymorphism array. The lists of differentially expressed proteins and genes were merged, and shared lists were created, keeping only terms with concordant mRNA and protein expression. Enrichment analyses were performed on the shared lists. Cell lines Mel285 and Mel290 are separate from GNA-mutated cell lines and show downregulation of melanosome-related markers. Both lack typical UM mutations but each harbors four putatively deleterious variants in CTNNB1, PPP1R10, LIMCH1, and APC in Mel285 and ARID1A, PPP1R10, SPG11, and RNF43 in Mel290. The upregulated terms in Mel285 and Mel290 did not point to a convincing alternative origin. Mel285 shows loss of chromosomes 1p, 3p, partial 3q, 6, and partial 8p, whereas Mel290 shows loss of 1p and 6. Expression in the other 12 cell lines was related to BAP1 expression. Although Mel285 and Mel290 have copy number alterations that fit UM, multi-omics analyses show that they belong to a separate group compared to the other analyzed UM cell lines. Therefore, they may not be representative models to test potential therapeutic targets for UM.

Advancing Genetic Testing in Kidney Diseases: Report From a National Kidney Foundation Working Group

About 37 million people in the United States have chronic kidney disease, a disease that encompasses diseases of multiple causes. About 10% or more of kidney diseases in adults and about 70% of selected chronic kidney diseases in children are expected to be explained by genetic causes. Despite the advances in genetic testing and an increasing understanding of the genetic bases of certain kidney diseases, genetic testing in nephrology lags behind other medical fields. More understanding of the benefits and logistics of genetic testing is needed to advance the implementation of genetic testing in chronic kidney diseases. Accordingly, the National Kidney Foundation convened a Working Group of experts with diverse expertise in genetics, nephrology, and allied fields to develop recommendations for genetic testing for monogenic disorders and to identify genetic risk factors for oligogenic and polygenic causes of kidney diseases. Algorithms for clinical decision making on genetic testing and a road map for advancing genetic testing in kidney diseases were generated. An important aspect of this initiative was the use of a modified Delphi process to reach group consensus on the recommendations. The recommendations and resources described herein provide support to nephrologists and allied health professionals to advance the use of genetic testing for diagnosis and screening of kidney diseases.

САРКОИДОЗ, ТРУДНОСТИ ДИАГНОСТИКИ

The incidence of sarcoidosis in Russia has not been studied enough. The clinical signs of sarcoidosis are diverse, and the lack of specific diagnostic tests makes noninvasive diagnosis difficult. In general therapeutic practice, in the case of an atypical course of the disease, diagnosis is complicated by the need for a differential diagnosis with many syndrome-like diseases. The etiology of sarcoidosis is still unknown. According to recent concepts, the cause of its occurrence cannot be considered a single factor, it is a combination of genetic, environmental, infectious and immunological causes. In this article, the author examines the main difficulties faced by doctors in the diagnosis of sarcoidosis. The clinical manifestations of the disease are analyzed, as well as methods of its detection, such as bronchoscopy, biopsy and laboratory tests. Possible diagnostic errors and how to avoid them are also considered. Understanding these difficulties will help improve the diagnosis and treatment of sarcoidosis, leading to more effective disease management.