Search Results (49)

Background: The prevalence of BARD1 mutations in breast and ovarian cancers varies across different ethnic groups. Evaluating the cancer risk and clinical significance of BARD1 mutations in the local Chinese patients with breast cancer, ovarian cancer, or both is clinically important for designing an appropriate surveillance scheme. Methods: This study used a 30 gene panel to identify BARD1 germline mutations in 2658 breast and ovarian cancer patients. Results: Among this cohort, the BARD1 mutation prevalence was 0.45% for breast cancer and 0.29% for ovarian cancer. In our 12 mutation carriers, we identified eight types of mutation variants, including three novel mutations. BARD1 mutation carriers were more likely to have a family history of liver, prostate, and cervical cancers (p-values = 0.004, 0.018, and 0.037, respectively) than patients who tested negative for mutations. Among the BARD1 mutants, the majority of the breast tumors were invasive ductal carcinoma (NOS type) (10/11, 90.9%) of high-grade disease (9/9, 100%) and half of them were triple-negative breast cancer (5/10, 50%). Conclusions: Although the prevalence of BARD1 mutations is low and the penetrance is incomplete, we recommend including BARD1 in the test panel for breast cancer patients. Our data suggest that more comprehensive surveillance management may be considered in mutation carriers due to the familial aggregation of a relatively wide spectrum of cancers. Full article

About 10% of all forms of melanoma occur in a familial context and may be due to germline predisposing mutations transmitted as autosomal dominant traits within the affected families. CDKN2A is a highly penetrant gene associated to familial melanomas, being responsible of up to 40% of the cases. Other high, moderate, and low penetrance genes are being discovered, even if their own contribution to melanoma risk is still under debate. Indeed, next generation sequencing-based strategies enable large genomic regions to be analyzed, thus identifying novel candidate genes. These strategies, in diagnostic settings, may also improve the identification of the hereditary cases between all melanomas. The identification of the at-risk subjects gives an important opportunity for cancer surveillance in order to reduce the risk of onset and/or make early diagnosis. In addition, the identification of molecular biomarkers may drive the future development of specific targeted therapies, as already done for other inherited cancer syndromes. Here, we summarize the state of the art regarding the molecular basis of the hereditary susceptibility to develop melanoma. Full article

Multigene panel testing for hereditary breast and ovarian cancer is becoming a standard in medical care. Recent studies highlight the importance of pathogenic variants in genes with moderate or low penetrance. 255 consecutive breast cancer cases who met the criteria for genetic testing were approached by next-generation sequencing. From 104 pathogenic mutations identified, 21 were in moderate-risk genes, three in low-risk genes and eight in the group with insufficient evidence genes. The most frequent PVs in moderate-risk genes were in the CHEK2 gene—Checkpoint kinase 2 gene (13 cases), the ATM gene—Ataxia-telangiectasia Mutated gene (six cases), BARD1—BRCA1-associated ring domain 1 gene (one case) and RAD 51C–radiation sensitive 51 Paralog C—(one case) genes. Among the low-risk genes, we identified only three pathogenic mutations (two in MSH1 gene—melanocyte-stimulating hormone gene—and one in MLH1 gene—MutL homolog 1 gene). Reporting on low-risk mutations and those with insufficient evidence regarding breast cancer risk is valuable to enable a more comprehensive view of genetic factors influencing disease development and improve screening protocols, tailor diagnostic strategies, and individualize treatment plans. This approach also enhances our understanding of BC risk in various populations, potentially leading to new insights into genetic contributions to cancer and the refinement of risk models for patient care. Full article

Neutron beams, being electrically neutral and highly penetrating, offer unique advantages for the irradiation of biological species such as plants, seeds, and microorganisms. We comprehensively investigated the potential of neutron irradiation for inducing genetic mutations by using simulations of spallation, reactor, and compact neutron sources based on J-PARC BL10, the JRR-3 TNRF, and KUANS. We analyzed neutron flux, energy deposition rates, and Linear Energy Transfer (LET) distributions. The KUANS simulation demonstrated the highest dose rate of 17 Gy/h, significantly surpassing that obtained at BL10, due to the large solid angle achieved with optimal sample placement. The findings highlight KUANS’s suitability for efficiently inducing specific genetic mutations and neutron breeding, particularly for inducing targeted mutations in biological samples, also on account of its LET range of 20–70 keV/μm. Our results emphasize the importance of choosing neutron sources based on LET requirements to maximize mutation induction efficiency. This research study shows the potential of compact neutron sources such as KUANS for effective biological irradiation and neutron breeding, offering a viable alternative to larger facilities. The neutron filters used at BL10 and the TNRF effectively exclude low-energy neutrons while keeping the high-LET component. The neutron capture reaction, ¹⁴N(n,p)¹⁴C, was found to be the main dose contributor under thermal neutron-dominated conditions. Full article

Background. Breast cancer remains a leading cause of cancer-related death among women, with genetic mutations playing a key role. While high-penetrance mutations are well-studied, moderate-to-low-penetrance mutations, which present challenges in clinical decision-making and patient outcomes, are less understood. This study explores the quality of life of breast cancer patients with moderate-penetrance mutations, focusing on the psychosocial and physical consequences of mastectomy and reconstruction to improve patient-centered care. Materials and Methods. A cohort of 620 breast cancer patients treated at Regina Maria Private Health Network, Bucharest, between January 2022 and July 2024 was identified. From this group, 61 patients were selected based on the following criteria: (1) meeting NCCN genetic testing guidelines, (2) carrying moderate-to-low-penetrance mutations, (3) undergoing bilateral mastectomy with double reconstruction, and (4) agreeing to complete a modified version of the BREAST-Q questionnaire. Genetic testing was performed using a 125-gene next-generation sequencing panel. Statistical analyses included non-parametric tests to examine group differences and correlations. Results. Significant correlations were found between several factors. Emotional distress was positively correlated with concerns for family, while couple relationships and financial burden showed a strong positive association. Negative correlations were found between couple relationships and self-concept. Distress levels varied, with “Interference with personal relationships” causing more distress than “Impact on employment”, and financial burden causing more distressing than impact on sexuality. Conclusions. Prophylactic mastectomy significantly reduces cancer risk for women with moderate-penetrance mutations. This study highlights the relationship between surgical choices and quality-of-life factors, advancing personalized prevention strategies and emphasizing patient-centered care. Full article

Genetically encoded voltage indicators (GEVIs) allow for the cell-type-specific real-time imaging of neuronal membrane potential dynamics, which is essential to understanding neuronal information processing at both cellular and circuit levels. Among GEVIs, near-infrared-shifted GEVIs offer faster kinetics, better tissue penetration, and compatibility with optogenetic tools, enabling all-optical electrophysiology in complex biological contexts. In our previous work, we employed the directed molecular evolution of microbial rhodopsin Archaerhodopsin-3 (Arch-3) in mammalian cells to develop a voltage sensor called Archon1. Archon1 demonstrated excellent membrane localization, signal-to-noise ratio (SNR), sensitivity, kinetics, and photostability, and full compatibility with optogenetic tools. However, Archon1 suffers from low brightness and requires high illumination intensities, which leads to tissue heating and phototoxicity during prolonged imaging. In this study, we aim to improve the brightness of this voltage sensor. We performed random mutation on a bright Archon derivative and identified a novel variant, monArch, which exhibits satisfactory voltage sensitivity (4~5% ΔF/F_AP) and a 9-fold increase in basal brightness compared with Archon1. However, it is hindered by suboptimal membrane localization and compromised voltage sensitivity. These challenges underscore the need for continued optimization to achieve an optimal balance of brightness, stability, and functionality in rhodopsin-based voltage sensors. Full article

In today’s world, with its continuing advancements in genetics, the identification of Lynch syndrome (LS) increasingly relies on sophisticated genetic testing techniques. Most guidelines recommend a tailored surveillance program, as well as personalized prophylactic and therapeutic approaches, according to the type of dMMR gene mutation. Carriers of path_MLH1 and path_MSH2 genes have a higher risk of developing colorectal cancer (CRC), despite intensive colonoscopic surveillance. Conversely, carriers of path_MSH6 and path_PMS2 genes have a lower risk of developing CRC, which may be due to their lower penetrance and later age of onset. Thus, carriers of path_MLH1 or path_MSH2 would theoretically derive greater benefits from total colectomy, compared to low-risk carriers (path_MSH6 and path_PMS2), in which colonoscopic surveillance might achieve an efficient prophylaxis. Furthermore, regarding the risk of endometrial/ovarian cancer development, there is a global agreement to offer both hysterectomy and bilateral salpingo-oophorectomy to path_MLH1, path_MSH2 and path_MSH6 carriers after the age of 40. In patients with CRC, preoperative knowledge of the diagnosis of LS is of tremendous importance, due to the high risk of metachronous CRC. However, this risk depends on the type of dMMR gene mutation. For carriers of the high-risk variants (MLH1, MSH2 and EPCAM) who have already developed colon cancer, it is strongly recommended a subtotal or total colectomy is performed, while partial colectomy followed by endoscopic surveillance is an appropriate management approach to treat colon cancer in carriers of the low-risk variants (MSH6 and PMS2). On the other hand, extended surgery for index rectal cancer (such as total proctocolectomy) is less effective than extended surgery for index colon cancer from the point of view of metachronous CRC risk reduction, and is associated with a decreased quality of life. Full article

Maturity-onset diabetes of the young (MODY) represents the most frequent form of monogenic diabetes mellitus (DM), currently classified in 14 distinct subtypes according to single gene mutations involved in the differentiation and function of pancreatic β-cells. A significant proportion of MODY has unknown etiology, suggesting that the genetic landscape is still to be explored. Recently, novel potentially MODY-causal genes, involved in the differentiation and function of β-cells, have been identified, such as RFX6, NKX2.2, NKX6.1, WFS1, PCBD1, MTOR, TBC1D4, CACNA1E, MNX1, AKT2, NEUROG3, EIF2AK3, GLIS3, HADH, and PTF1A. Genetic and clinical features of MODY variants remain highly heterogeneous, with no direct genotype–phenotype correlation, especially in the low-penetrant subtypes. This is a narrative review of the literature aimed at describing the current state-of-the-art of the novel likely MODY-associated variants. For a deeper understanding of MODY complexity, we also report some related controversies concerning the etiological role of some of the well-known pathological genes and MODY inheritance pattern, as well as the rare association of MODY with autoimmune diabetes. Due to the limited data available, the assessment of MODY-related genes pathogenicity remains challenging, especially in the setting of rare and low-penetrant subtypes. In consideration of the crucial importance of an accurate diagnosis, prognosis and management of MODY, more studies are warranted to further investigate its genetic landscape and the genotype–phenotype correlation, as well as the pathogenetic contribution of the nongenetic modifiers in this cohort of patients. Full article

Hemochromatosis (HC) is the main genetic disorder of iron overload and is regarded as metal-related human toxicosis. HC may result from HFE and rare non-HFE gene mutations, causing hepcidin deficiency or, sporadically, hepcidin resistance. This review focuses on HFE-related HC. The illness presents a strong biochemical penetrance, but its prevalence is low. Unfortunately, the majority of patients with HC remain undiagnosed at their disease-curable stage. The main aim of HC management is to prevent iron overload in its early phase and remove excess iron from the body by phlebotomy in its late stage. Raising global awareness of HC among health staff, teaching them how not to overlook early HC manifestations, and paying attention to careful patient monitoring remain critical management strategies for preventing treatment delays, upgrading its efficacy, and improving patient prognosis. Full article

A novel rare mutation in the pore region of Nav1.5 channels (p.L889V) has been found in three unrelated Spanish families that produces quite diverse phenotypic manifestations (Brugada syndrome, conduction disease, dilated cardiomyopathy, sinus node dysfunction, etc.) with variable penetrance among families. We clinically characterized the carriers and recorded the Na⁺ current (I_Na) generated by p.L889V and native (WT) Nav1.5 channels, alone or in combination, to obtain further insight into the genotypic–phenotypic relationships in patients carrying SCN5A mutations and in the molecular determinants of the Nav1.5 channel function. The variant produced a strong dominant negative effect (DNE) since the peak I_Na generated by p.L889V channels expressed in Chinese hamster ovary cells, either alone (−69.4 ± 9.0 pA/pF) or in combination with WT (−62.2 ± 14.6 pA/pF), was significantly (n ≥ 17, p < 0.05) reduced compared to that generated by WT channels alone (−199.1 ± 44.1 pA/pF). The mutation shifted the voltage dependence of channel activation and inactivation to depolarized potentials, did not modify the density of the late component of I_Na, slightly decreased the peak window current, accelerated the recovery from fast and slow inactivation, and slowed the induction kinetics of slow inactivation, decreasing the fraction of channels entering this inactivated state. The membrane expression of p.L889V channels was low, and in silico molecular experiments demonstrated profound alterations in the disposition of the pore region of the mutated channels. Despite the mutation producing a marked DNE and reduction in the I_Na and being located in a critical domain of the channel, its penetrance and expressivity are quite variable among the carriers. Our results reinforce the argument that the incomplete penetrance and phenotypic variability of SCN5A loss-of-function mutations are the result of a combination of multiple factors, making it difficult to predict their expressivity in the carriers despite the combination of clinical, genetic, and functional studies. Full article

Radioactivity is a process in which the nuclei of unstable atoms spontaneously decay, producing other nuclei and releasing energy in the form of ionizing radiation in the form of alpha (α) and beta (β) particles as well as the emission of gamma (γ) electromagnetic waves. People may be exposed to radiation in various forms, as casualties of nuclear accidents, workers in power plants, or while working and using different radiation sources in medicine and health care. Acute radiation syndrome (ARS) occurs in subjects exposed to a very high dose of radiation in a very short period of time. Each form of radiation has a unique pathophysiological effect. Unfortunately, higher organisms—human beings—in the course of evolution have not acquired receptors for the direct “capture” of radiation energy, which is transferred at the level of DNA, cells, tissues, and organs. Radiation in biological systems depends on the amount of absorbed energy and its spatial distribution, particularly depending on the linear energy transfer (LET). Photon radiation with low LET leads to homogeneous energy deposition in the entire tissue volume. On the other hand, radiation with a high LET produces a fast Bragg peak, which generates a low input dose, whereby the penetration depth into the tissue increases with the radiation energy. The consequences are mutations, apoptosis, the development of cancer, and cell death. The most sensitive cells are those that divide intensively—bone marrow cells, digestive tract cells, reproductive cells, and skin cells. The health care system and the public should raise awareness of the consequences of ionizing radiation. Therefore, our aim is to identify the consequences of ARS taking into account radiation damage to the respiratory system, nervous system, hematopoietic system, gastrointestinal tract, and skin. Full article

Breast cancer is a global health problem. It is an age-dependent disease, but cases of early-onset breast cancer (eBC) are gradually increasing. There are many unresolved questions regarding eBC risk factors, mechanisms of development and screening. Only 10% of eBC cases are due to mutations in the BRCA1/BRCA2 genes, and 90% have a more complex genetic background. This poses a significant challenge to timely cancer detection in young women and highlights the need for research and awareness. Therefore, identifying genetic risk factors for eBC is essential to solving these problems. This study represents an association analysis of 144 eBC cases and 163 control participants to identify genetic markers associated with eBC risks in Kazakh women. We performed a two-stage approach in association analysis to assess genetic predisposition to eBC. First-stage genome-wide association analysis revealed two risk intronic loci in the CHI3L2 gene (p = 5.2 × 10⁻⁶) and MGAT5 gene (p = 8.4 × 10⁻⁶). Second-stage exonic polymorphisms haplotype analysis showed significant risks for seven haplotypes (p < 9.4 × 10⁻⁴). These results point to the importance of studying medium- and low-penetrant genetic markers in their haplotype combinations for a detailed understanding of the role of detected genetic markers in eBC development and prediction. Full article

Acute intermittent porphyria (AIP) is a metabolic disorder caused by mutations in the porphobilinogen deaminase (PBGD) gene, encoding the third enzyme of the heme synthesis pathway. Although AIP is characterized by low clinical penetrance (~1% of PBGD mutation carriers), patients with clinically stable disease report chronic symptoms and frequently show insulin resistance. This study aimed to evaluate the beneficial impact of nutritional interventions on correct carbohydrate dysfunctions in a mouse model of AIP that reproduces insulin resistance and altered glucose metabolism. The addition of spores of Bacillus coagulans in drinking water for 12 weeks modified the gut microbiome composition in AIP mice, ameliorated glucose tolerance and hyperinsulinemia, and stimulated fat disposal in adipose tissue. Lipid breakdown may be mediated by muscles burning energy and heat dissipation by brown adipose tissue, resulting in a loss of fatty tissue and improved lean/fat tissue ratio. Probiotic supplementation also improved muscle glucose uptake, as measured using Positron Emission Tomography (PET) analysis. In conclusion, these data provide a proof of concept that probiotics, as a dietary intervention in AIP, induce relevant changes in intestinal bacteria composition and improve glucose uptake and muscular energy utilization. Probiotics may offer a safe, efficient, and cost-effective option to manage people with insulin resistance associated with AIP. Full article

Germline pathogenic variants (PVs) in the Ataxia Telangiectasia mutated (ATM) gene (MIM* 607585) increase the risk for breast, pancreatic, gastric, and prostatic cancer and, to a reduced extent, ovarian and colon cancer and melanoma, with moderate penetrance and variable expressivity. We describe a family presenting early-onset gastric cancer and harboring a heterozygous pathogenic ATM variant. The proband had gastric cancer (age 45) and reported a sister deceased due to diffuse gastric cancer (age 30) and another sister who developed diffuse gastric cancer (age 52) and ovarian serous cancer. Next generation sequencing for cancer susceptibility genes (APC, ATM, BRD1, BRIP1, CDH1, CDK4, CDKN2A, CHEK2, EPCAM, MLH1, MRE11, MSH2, MSH6, MUTYH, NBN, PALB2, PMS2, PTEN, RAD50, RAD51C, RAD51D, RECQL1, SMAD4, STK11, and TP53) was performed. Molecular analysis identified the truncating c.5944C>T, p.(Gln1982*) variant in the ATM (NM_000051.3; NP_000042.3) in the proband. The variant had segregated in the living affected sister and in the unaffected daughter of the deceased affected sister. Familial early-onset gastric cancer is an unusual presentation for ATM-related malignancies. Individual variants may result in different specific risks. Genotype–phenotype correlations are challenging given the low penetrance and variable expressivity. Careful family history assessments are pivotal for prevention planning and are strengthened by the availability of molecular diagnoses. Full article

The lungs of tuberculosis (TB) patients contain a spectrum of granulomatous lesions, ranging from solid and well-vascularized cellular granulomas to avascular caseous granulomas. In solid granulomas, current therapy kills actively replicating (AR) intracellular bacilli, while in low-vascularized caseous granulomas the low-oxygen tension stimulates aerobic and microaerophilic AR bacilli to transit into non-replicating (NR), drug-tolerant and extracellular stages. These stages, which do not have genetic mutations and are often referred to as persisters, are difficult to eradicate due to low drug penetration inside the caseum and mycobacterial cell walls. The sputum of TB patients also contains viable bacilli called differentially detectable (DD) cells that, unlike persisters, grow in liquid, but not in solid media. This review provides a comprehensive update on drug combinations killing in vitro AR and drug-tolerant bacilli (persisters and DD cells), and sterilizing Mycobacterium tuberculosis-infected BALB/c and caseum-forming C3HeB/FeJ mice. These observations have been important for testing new drug combinations in noninferiority clinical trials, in order to shorten the duration of current regimens against TB. In 2022, the World Health Organization, following the results of one of these trials, supported the use of a 4-month regimen for the treatment of drug-susceptible TB as a possible alternative to the current 6-month regimen. Full article