Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 3.997
Filter
1.
J Med Entomol ; 2024 Jul 06.
Article in English | MEDLINE | ID: mdl-38970363

ABSTRACT

Population genetic structure of arthropod disease vectors provides important information on vector movement and climate or other environmental variables that influence their distribution. This information is critical for data-driven vector control. In the first comprehensive study of the genetic structure of T. dimidiata s.l. (Latreille, 1811) we focus on an area of active transmission designated as a top priority for control. We examined a high number of specimens across a broad geographic area along the border of Guatemala and El Salvador including multiple spatial scales using a high number of genome-wide markers. Measuring admixture, pairwise genetic differentiation, and relatedness, we estimated the specimens represented three genetic clusters. We found evidence of movement (migration/gene flow) across all spatial scales with more admixture among locations in El Salvador than in Guatemala. Although there was significant isolation by distance, the 2 close villages in Guatemala showed either the most or least genetic variation indicating an additional role of environmental variables. Further, we found that social factors may be influencing the genetic structure. We demonstrated the power of genomic studies with a large number of specimens across a broad geographic area. The results suggest that for effective vector control movement must be considered on multiple spatial scales along with its contributing factors.

2.
Sci Adv ; 10(28): eadk2091, 2024 Jul 12.
Article in English | MEDLINE | ID: mdl-38996030

ABSTRACT

The mechanism by which interferon regulatory factor 8 (IRF8) mutation contributes to lymphomagenesis is unknown. We modeled IRF8 variants in B cell lymphomas and found that they affected the expression of regulators of antigen presentation. Expression of IRF8 mutants in murine B cell lymphomas suppressed CD4, but not CD8, activation elicited by antigen presentation and downmodulated CD74 and human leukocyte antigen (HLA) DM, intracellular regulators of antigen peptide processing/loading in the major histocompatibility complex (MHC) II. Concordantly, mutant IRF8 bound less efficiently to the promoters of these genes. Mice harboring IRF8 mutant lymphomas displayed higher tumor burden and remodeling of the tumor microenvironment, typified by depletion of CD4, CD8, and natural killer cells, increase in regulatory T cells and T follicular helper cells. Deconvolution of bulk RNA sequencing data from IRF8-mutant human diffuse large B cell lymphoma (DLBCL) recapitulated part of the immune remodeling detected in mice. We concluded that IRF8 mutations contribute to DLBCL biology by facilitating immune escape.


Subject(s)
Antigen Presentation , Antigens, Differentiation, B-Lymphocyte , Histocompatibility Antigens Class II , Interferon Regulatory Factors , Mutation , Interferon Regulatory Factors/genetics , Interferon Regulatory Factors/metabolism , Animals , Antigen Presentation/immunology , Antigen Presentation/genetics , Humans , Mice , Histocompatibility Antigens Class II/genetics , Histocompatibility Antigens Class II/immunology , Histocompatibility Antigens Class II/metabolism , Antigens, Differentiation, B-Lymphocyte/genetics , Antigens, Differentiation, B-Lymphocyte/metabolism , Lymphoma, B-Cell/genetics , Lymphoma, B-Cell/immunology , Tumor Microenvironment/immunology , Lymphoma, Large B-Cell, Diffuse/genetics , Lymphoma, Large B-Cell, Diffuse/immunology , Lymphoma, Large B-Cell, Diffuse/pathology , Cell Line, Tumor , Tumor Escape/genetics , Gene Expression Regulation, Neoplastic
3.
Am J Gastroenterol ; 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-39008539

ABSTRACT

BACKGROUND: A treat-to-target strategy for inflammatory bowel disease (IBD) recommends iterative treatment adjustments to achieve clinical and endoscopic remission. In asymptomatic patients with ongoing endoscopic activity, the risk/benefit balance of this approach is unclear, particularly with prior exposure to advanced therapies. METHODS: Using the RAND/UCLA Appropriateness Method, 9 IBD specialists rated appropriateness of changing therapy in 126 scenarios of asymptomatic patients with ulcerative colitis (UC) and Crohn's disease (CD) and active endoscopic disease. Disease extent and behavior, prior treatment, prior complications, and recent disease progression were considered, as were factors that might influence decision-making, including age and pregnancy. Ratings were collected via anonymous survey, discussed at an in-person meeting, and finalized in a second anonymous survey. RESULTS: Panelists rated change in therapy as appropriate (i.e., expected benefit sufficiently outweighs potential harms from continuing therapy) in 96/126 scenarios, generally in patients with progressive, complicated, and/or extensive disease, while changing therapy was rated uncertain in 27 scenarios of mild and/or stable disease. Changing therapy was rated inappropriate in UC patients with mild and stable disease previously exposed to ≥3 therapies or with improved endoscopic activity, and in CD patients with only scattered aphthous ulcers. The validated threshold for disagreement was not crossed for any scenario. Patient age >65 years and a plan for pregnancy in the next year might influence decision-making in some settings. CONCLUSION: Appropriateness ratings can help guide clinical decision-making about changing therapy to achieve endoscopic remission in asymptomatic patients with IBD until data from ongoing randomized studies are available.

4.
Pediatr Blood Cancer ; : e31188, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-39010280

ABSTRACT

People with sickle cell disease (SCD) often have emergency department (ED) revisits. The characteristics of people with SCD with ED revisits were assessed in this study using Medicaid administrative claims data from California and Georgia, representing 2794 and 3641 individuals with SCD, respectively. In both states, those with 6+ primary care provider (PCP) encounters had the highest percentage of ED revisits. In California, those with 6+ hematology encounters had the lowest percentage of individuals with an ED revisit; in Georgia, those with 1-2 hematology encounters. Increasing access to hematologic care may reduce ED revisits among people with SCD.

5.
Mol Genet Metab Rep ; 40: 101110, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39022300

ABSTRACT

Treatment of phenylketonuria (PKU) has evolved since the initial introduction of a phenylalanine (Phe) restricted diet. The most recent option for adults affected with PKU is treatment with an alternate enzyme, phenylalanine ammonia lyase (PAL), that metabolizes excess Phe. Proper management of all patients with PKU relies on accurate measurement of Phe levels in blood, to comply with guidance intended to minimize the neurological symptoms. Recently, our laboratory was notified of discrepant results for a patient with PKU who is treated with pegvaliase. Two specimens were collected at the same time but yielded unexpectedly different Phe concentrations. After exclusion of specimen mix-ups or analytical errors, we suspected that there was residual pegvaliase activity in the specimens continuing to degrade Phe after collection. To investigate this possibility, we performed spiking studies that showed the degradation of Phe over time at ambient temperatures. Sample preparation by protein crash appears to deactivate pegvaliase and prevents further Phe degradation. However, because pegvaliase deactivation would be required immediately following blood collection, appropriate mitigation measures must be implemented, including stringent pre-analytical requirements, alternate sample matrices such as dried blood spots, or point of care testing. Until then, health care professionals need to be cautious in their interpretation of Phe levels in their patients with PKU that are treated with pegvaliase.

6.
Arch Argent Pediatr ; : e202410431, 2024 07 11.
Article in Spanish | MEDLINE | ID: mdl-38967622

ABSTRACT

Latex allergy, or natural rubber latex allergy (NRLA), is a global health concern, even among the pediatric population, with symptoms varying in severity from mild to potentially life-threatening. Latex is derived from the Hevea Brasiliensis tree, producing twelve million tons annually for use in various everyday and medical products. Despite efforts to mitigate NRLA, its prevalence remains high, especially in at- risk groups such as children with spina bifida. Clinical manifestations include immediate and delayed symptoms, even anaphylactic reactions. Diagnosis involves a detailed medical history and specific tests. Prevention focuses on avoiding exposure, especially in medical and educational settings. Treatment, including immunotherapy, exhibits variable efficacy. NRLA has a strong negative impact on children's quality of life. The objective of this publication is to provide updated information and practical tools for the pediatrician's and allergist's practice.


La alergia al látex del caucho natural (ALCN) es un problema de salud global, incluso en población pediátrica, con síntomas de gravedad variable, desde leves hasta potencialmente mortales. El látex se obtiene del árbol Hevea brasiliensis; se producen doce millones de toneladas anuales que se utilizan en diversos productos cotidianos y médicos. A pesar de los esfuerzos para mitigar la ALCN, su prevalencia sigue siendo alta, especialmente en grupos de riesgo, como niños con espina bífida. Las manifestaciones clínicas incluyen síntomas inmediatos y retardados, hasta reacciones anafilácticas. El diagnóstico requiere una historia clínica detallada y pruebas específicas. La prevención se centra en evitar la exposición, especialmente en entornos médicos y escolares. El tratamiento, incluida la inmunoterapia, muestra eficacia variable. La ALCN tiene un fuerte impacto negativo en la calidad de vida. El objetivo de esta publicación es proveer información actualizada y herramientas prácticas para el consultorio del pediatra y el alergólogo.

8.
JAMA Surg ; 2024 Jul 17.
Article in English | MEDLINE | ID: mdl-39018050

ABSTRACT

Importance: The ability to pursue family planning goals is integral to gender equity in any field. Procedural specialties pose occupational risks to pregnancy. As the largest procedural specialty, general surgery provides an opportunity to understand family planning, workplace support for parenthood, obstetric outcomes, and the impact of these factors on workforce well-being, gender equity, and attrition. Objective: To examine pregnancy and parenthood experiences, including mistreatment and obstetric outcomes, among a cohort of US general surgical residents. Design, Setting, and Participants: This cohort study involved a cross-sectional national survey of general surgery residents in all programs accredited by the Accreditation Council for Graduate Medical Education after the 2021 American Board of Surgery In-Training Examination. Female respondents who reported a pregnancy and male respondents whose partners were pregnant during clinical training were queried about pregnancy- and parenthood-based mistreatment, obstetric outcomes, and current well-being (burnout, thoughts of attrition, suicidality). Main Outcomes and Measures: Primary outcomes included obstetric complications and postpartum depression compared between female residents and partners of male residents. Secondary outcomes included perceptions about support for family planning, pregnancy, or parenthood; assisted reproductive technology use; pregnancy/parenthood-based mistreatment; neonatal complications; and well-being, compared between female and male residents. Results: A total of 5692 residents from 325 US general surgery programs participated (81.2% response rate). Among them, 957 residents (16.8%) reported a pregnancy during clinical training (692/3097 [22.3%] male vs 265/2595 [10.2%] female; P < .001). Compared with male residents, female residents more frequently delayed having children because of training (1201/2568 [46.8%] females vs 1006/3072 [32.7%] males; P < .001) and experienced pregnancy/parenthood-based mistreatment (132 [58.1%] females vs 179 [30.5%] males; P < .001). Compared with partners of male residents, female residents were more likely to experience obstetric complications (odds ratio [OR], 1.42; 95% CI, 1.04-1.96) and postpartum depression (OR, 1.63; 95% CI, 1.11-2.40). Pregnancy/parenthood-based mistreatment was associated with increased burnout (OR, 2.03; 95% CI, 1.48-2.78) and thoughts of attrition (OR, 2.50; 95% CI, 1.61-3.88). Postpartum depression, whether in female residents or partners of male residents, was associated with resident burnout (OR, 1.93; 95% CI, 1.27-2.92), thoughts of attrition (OR, 2.32; 95% CI, 1.36-3.96), and suicidality (OR, 5.58; 95% CI, 2.59-11.99). Conclusions and Relevance: This study found that pregnancy/parenthood-based mistreatment, obstetric complications, and postpartum depression were associated with female gender, likely driving gendered attrition. Systematic change is needed to protect maternal-fetal health and advance gender equity in procedural fields.

9.
Viruses ; 16(6)2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38932251

ABSTRACT

Pentasilver hexaoxoiodate (Ag5IO6) has broad-spectrum antimicrobial efficacy, including the long-term prevention of microbial adherence, the rapid killing of planktonic microorganisms, and the elimination of mature biofilms. This study's goal was to determine whether it may also have antiviral activity against structurally distinct viruses. Ag5IO6 was tested following ASTM E1052-20, Standard Practice to Assess the Activity of Microbicides Against Viruses in Suspension, against adenovirus type 5, murine norovirus, poliovirus type 1, SARS-CoV-2 (original), and SARS-CoV-2 (omicron) (host cells: H1HeLa, RAW 264.7, LLC-MK2, Vero E6, and Vero E6, respectively). A 0.1 g/mL Ag5IO6 suspension was prepared and the viruses were exposed for 30 min, 4 h, or 24 h. Exposure to Ag5IO6 resulted in complete kill of SARS-CoV-2 (omicron) within 30 min, as well as complete kill of both SARS-CoV-2 (original) and the murine norovirus within 4 h. Ag5IO6 showed increasing activity over time against the adenovirus, but did not achieve a 3-log reduction within 24 h, and showed no antiviral activity against the poliovirus. These results demonstrate that Ag5IO6 has antiviral activity against medically important viruses, in addition to its well-characterized antimicrobial activity, suggesting that it may be valuable in situations where the prevention or simultaneous treatment of microbes and viruses are necessary.


Subject(s)
Antiviral Agents , SARS-CoV-2 , Antiviral Agents/pharmacology , Antiviral Agents/chemistry , Animals , Mice , Chlorocebus aethiops , Humans , SARS-CoV-2/drug effects , Vero Cells , Silver Compounds/pharmacology , Silver Compounds/chemistry , Cell Line , Poliovirus/drug effects , Norovirus/drug effects , RAW 264.7 Cells
10.
Matern Child Nutr ; : e13684, 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38943254

ABSTRACT

Approximately half of pregnant women in India are anemic, representing over 7.5 million women. Few studies have assessed the relationship between multiple micronutrient deficiencies and anemia during pregnancy or the trajectory of hemoglobin (Hb) during pregnancy in low-resource settings. We enrolled 200 pregnant women from the Maternal and Newborn Health (MNH) registry, a population-based pregnancy and birth registry in Eastern Maharashtra, India to address these gaps. The women provided capillary (finger-prick) and venous blood specimens at enrollment (<15 weeks), and a second capillary specimen in the 3rd trimester (>27 weeks). Capillary specimens were analyzed at the time of collection with a HemoCue Hb 201+; venous specimens were shipped on dry ice to a laboratory for cyanmethemoglobin assessment. In the 1st trimester, mean Hb concentration and anemia (Hb<11.0 g/dL) prevalence using capillary specimens were 10.9 ± 1.5 g/dL and 51.1%; mean Hb concentration using venous blood specimens was estimated to be 11.3 ± 1.3 g/dL and anemia prevalence was 37.5%. The prevalence of iron, vitamin B12 and folate deficiencies were 40%, 30% and 0%, respectively. Among women with anemia in the 1st trimester (venous blood), 56% had concurrent iron deficiency (inflammation-adjusted serum ferritin <15 µg/L) indicating that their anemia may be amenable to iron supplementation. In total, 21% of women had ID and anemia, 19% ID in the absence of anemia, 16.5% anemia in the absence of ID and 43.5% had neither. By the 3rd trimester, mean Hb from capillary specimens had declined to 10.1 ± 1.35 g/dL and anemia prevalence increased to 70.7%, despite 99.4% mothers reporting receipt of iron-folic acid (IFA) supplements during her current pregnancy, and 83.9% reporting IFA consumption the previous day. Significant predictors of anemia in the 1st trimester (both venous and capillary) included the number of weeks gestation at the time of Hb assessment and inflammation-adjusted serum ferritin. For 3rd trimester anemia, significant predictors included 1st trimester height, BMI and IFA consumption during the 3rd trimester (but not 1st trimester micronutrient biomarkers), indicating that IFA supplementation over the course of pregnancy may have influenced micronutrient status and anemia risk. Our findings highlight the severity of the burden of anemia and micronutrient deficiencies in Eastern Maharashtra, but also highlight that in many cases, ID and anemia affect different individuals. Preventing and managing anemia in pregnancy in India will require strengthening both clinical and community-based strategies targeting iron deficiency, as well as other causes of anemia.

11.
J Immunol Methods ; 530: 113698, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38823574

ABSTRACT

There is a critical need to understand the effectiveness of serum elicited by different SARS-CoV-2 vaccines against SARS-CoV-2 variants. We describe the generation of reference reagents comprised of post-vaccination sera from recipients of different primary vaccines with or without different vaccine booster regimens in order to allow standardized characterization of SARS-CoV-2 neutralization in vitro. We prepared and pooled serum obtained from donors who received a either primary vaccine series alone, or a vaccination strategy that included primary and boosted immunization using available SARS-CoV-2 mRNA vaccines (BNT162b2, Pfizer and mRNA-1273, Moderna), replication-incompetent adenovirus type 26 vaccine (Ad26.COV2·S, Johnson and Johnson), or recombinant baculovirus-expressed spike protein in a nanoparticle vaccine plus Matrix-M adjuvant (NVX-CoV2373, Novavax). No subjects had a history of clinical SARS-CoV-2 infection, and sera were screened with confirmation that there were no nucleocapsid antibodies detected to suggest natural infection. Twice frozen sera were aliquoted, and serum antibodies were characterized for SARS-CoV-2 spike protein binding (estimated WHO antibody binding units/ml), spike protein competition for ACE-2 binding, and SARS-CoV-2 spike protein pseudotyped lentivirus transduction. These reagents are available for distribution to the research community (BEI Resources), and should allow the direct comparison of antibody neutralization results between different laboratories. Further, these sera are an important tool to evaluate the functional neutralization activity of vaccine-induced antibodies against emerging SARS-CoV-2 variants of concern. IMPORTANCE: The explosion of COVID-19 demonstrated how novel coronaviruses can rapidly spread and evolve following introduction into human hosts. The extent of vaccine- and infection-induced protection against infection and disease severity is reduced over time due to the fall in concentration, and due to emerging variants that have altered antibody binding regions on the viral envelope spike protein. Here, we pooled sera obtained from individuals who were immunized with different SARS-CoV-2 vaccines and who did not have clinical or serologic evidence of prior infection. The sera pools were characterized for direct spike protein binding, blockade of virus-receptor binding, and neutralization of spike protein pseudotyped lentiviruses. These sera pools were aliquoted and are available to allow inter-laboratory comparison of results and to provide a tool to determine the effectiveness of prior vaccines in recognizing and neutralizing emerging variants of concern.


Subject(s)
2019-nCoV Vaccine mRNA-1273 , Antibodies, Neutralizing , Antibodies, Viral , BNT162 Vaccine , COVID-19 Vaccines , COVID-19 , Neutralization Tests , SARS-CoV-2 , Humans , SARS-CoV-2/immunology , Antibodies, Viral/blood , Antibodies, Viral/immunology , COVID-19/prevention & control , COVID-19/immunology , COVID-19/virology , Antibodies, Neutralizing/blood , Antibodies, Neutralizing/immunology , COVID-19 Vaccines/immunology , COVID-19 Vaccines/administration & dosage , 2019-nCoV Vaccine mRNA-1273/immunology , BNT162 Vaccine/immunology , BNT162 Vaccine/administration & dosage , Spike Glycoprotein, Coronavirus/immunology , Reference Standards , Immunization, Secondary , Vaccination , Ad26COVS1/immunology
12.
Toxicon ; 247: 107831, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38936670

ABSTRACT

Establishing humane endpoints to minimize animal suffering in studies on snake venom toxicity and antivenom potency tests is crucial. Our findings reveal that Swiss mice exhibit early temperature drop following exposure to different snake venoms and combinations of venoms and antivenoms, predicting later mortality. Evaluating temperature we can identify within 3 h post-inoculation, the animals that will not survive in a period of 48 h. Implementing temperature as a criterion would significantly reduce animal suffering in these studies without compromising the outcomes.

13.
J Am Coll Surg ; 2024 Jun 26.
Article in English | MEDLINE | ID: mdl-38920301

ABSTRACT

BACKGROUND: The demands of surgical training present challenges for work-life integration (WLI). We sought to identify factors associated with work-life conflicts and to understand how programs support WLI. STUDY DESIGN: A cross-sectional national survey conducted after the 2020 American Board of Surgery In-Training Examination queried 4 WLI items. Multivariable regression models evaluated factors associated with (1) work-life conflicts and (2) well-being (career dissatisfaction, burnout, thoughts of attrition, suicidality). Semi-structured interviews conducted with faculty and residents from 15 general surgery programs were analyzed to identify strategies for supporting WLI. RESULTS: Of 7,233 residents (85.5% response rate) 5,133 had data available on work-life conflicts. 44.3% reported completing non-educational task-work at home, 37.6% were dissatisfied with time for personal life (e.g., hobbies), 51.6% with maintaining healthy habits (e.g., exercise), and 48.0% with performing routine health maintenance (e.g., dentist). In multivariable analysis, parents and female residents were more likely to report work-life conflicts (all p<0.05). After adjusting for other risk factors (e.g., duty-hour violations, and mistreatment), residents with work-life conflicts remained at increased risk for career dissatisfaction, burnout, thoughts of attrition, and suicidality (all p<0.05). Qualitative analysis revealed interventions for supporting WLI including (1) protecting time for health maintenance (e.g., therapy); (2) explicitly supporting life outside of work (e.g., prioritizing time with family); and (3) allowing meaningful autonomy in scheduling (e.g., planning for major life events). CONCLUSIONS: Work-life conflicts are common among surgical residents and are associated with poor resident well-being. Well-designed program-level interventions have the potential to support WLI in surgical residency.

14.
Nat Ecol Evol ; 8(7): 1216-1223, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38831016

ABSTRACT

Although invasive alien species have long been recognized as a major threat to nature and people, until now there has been no comprehensive global review of the status, trends, drivers, impacts, management and governance challenges of biological invasions. The Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) Thematic Assessment Report on Invasive Alien Species and Their Control (hereafter 'IPBES invasive alien species assessment') drew on more than 13,000 scientific publications and reports in 15 languages as well as Indigenous and local knowledge on all taxa, ecosystems and regions across the globe. Therefore, it provides unequivocal evidence of the major and growing threat of invasive alien species alongside ambitious but realistic approaches to manage biological invasions. The extent of the threat and impacts has been recognized by the 143 member states of IPBES who approved the summary for policymakers of this assessment. Here, the authors of the IPBES assessment outline the main findings of the IPBES invasive alien species assessment and highlight the urgency to act now.


Subject(s)
Biodiversity , Conservation of Natural Resources , Introduced Species , Animals , Ecosystem
15.
Arch Cardiol Mex ; 94(Supl 2): 1-52, 2024.
Article in English | MEDLINE | ID: mdl-38848096

ABSTRACT

The diagnostic criteria, treatments at the time of admission, and drugs used in patients with acute coronary syndrome are well defined in countless guidelines. However, there is uncertainty about the measures to recommend during patient discharge planning. This document brings together the most recent evidence and the standardized and optimal treatment for patients at the time of discharge from hospitalization for an acute coronary syndrome, for comprehensive and safe care in the patient's transition between care from the acute event to the outpatient care, with the aim of optimizing the recovery of viable myocardium, guaranteeing the most appropriate secondary prevention, reducing the risk of a new coronary event and mortality, as well as the adequate reintegration of patients into daily life.


Los criterios diagnósticos, los tratamientos en el momento de la admisión y los fármacos utilizados en pacientes con síndrome coronario agudo están bien definidos en innumerables guías. Sin embargo, existe incertidumbre acerca de las medidas para recomendar durante la planificación del egreso de los pacientes. Este documento reúne las evidencias más recientes y el tratamiento estandarizado y óptimo para los pacientes al momento del egreso de una hospitalización por un síndrome coronario agudo, para un cuidado integral y seguro en la transición del paciente entre la atención del evento agudo y el cuidado ambulatorio, con el objetivo de optimizar la recuperación de miocardio viable, garantizar la prevención secundaria más adecuada, reducir el riesgo de un nuevo evento coronario y la mortalidad, así como la adecuada reinserción de los pacientes en la vida cotidiana.


Subject(s)
Acute Coronary Syndrome , Patient Discharge , Acute Coronary Syndrome/therapy , Acute Coronary Syndrome/diagnosis , Humans , Latin America , Practice Guidelines as Topic
20.
Nat Commun ; 15(1): 4681, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38824190

ABSTRACT

The telomere sequence, TTAGGG, is conserved across all vertebrates and plays an essential role in suppressing the DNA damage response by binding a set of proteins termed shelterin. Changes in the telomere sequence impair shelterin binding, initiate a DNA damage response, and are toxic to cells. Here we identify a family with a variant in the telomere template sequence of telomerase, the enzyme responsible for telomere elongation, that led to a non-canonical telomere sequence. The variant is inherited across at least one generation and one family member reports no significant medical concerns despite ~9% of their telomeres converting to the novel sequence. The variant template disrupts telomerase repeat addition processivity and decreased the binding of the telomere-binding protein POT1. Despite these disruptions, the sequence is readily incorporated into cellular chromosomes. Incorporation of a variant sequence prevents POT1-mediated inhibition of telomerase suggesting that incorporation of a variant sequence may influence telomere addition. These findings demonstrate that telomeres can tolerate substantial degeneracy while remaining functional and provide insights as to how incorporation of a non-canonical telomere sequence might alter telomere length dynamics.


Subject(s)
Pedigree , Shelterin Complex , Telomerase , Telomere-Binding Proteins , Telomere , Humans , Telomere/metabolism , Telomere/genetics , Telomere-Binding Proteins/metabolism , Telomere-Binding Proteins/genetics , Shelterin Complex/metabolism , Telomerase/genetics , Telomerase/metabolism , Male , Female , Telomere Homeostasis/genetics , Base Sequence , Adult
SELECTION OF CITATIONS
SEARCH DETAIL
...