Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 159
Filtrar
Más filtros

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
PLoS Genet ; 19(3): e1010387, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36972313

RESUMEN

BACKGROUND: Tuberculosis (TB) remains a major public health problem globally, even compared to COVID-19. Genome-wide studies have failed to discover genes that explain a large proportion of genetic risk for adult pulmonary TB, and even fewer have examined genetic factors underlying TB severity, an intermediate trait impacting disease experience, quality of life, and risk of mortality. No prior severity analyses used a genome-wide approach. METHODS AND FINDINGS: As part of our ongoing household contact study in Kampala, Uganda, we conducted a genome-wide association study (GWAS) of TB severity measured by TBScore, in two independent cohorts of culture-confirmed adult TB cases (n = 149 and n = 179). We identified 3 SNPs (P<1.0 x 10-7) including one on chromosome 5, rs1848553, that was GWAS significant (meta-analysis p = 2.97x10-8). All three SNPs are in introns of RGS7BP and have effect sizes corresponding to clinically meaningful reductions in disease severity. RGS7BP is highly expressed in blood vessels and plays a role in infectious disease pathogenesis. Other genes with suggestive associations defined gene sets involved in platelet homeostasis and transport of organic anions. To explore functional implications of the TB severity-associated variants, we conducted eQTL analyses using expression data from Mtb-stimulated monocyte-derived macrophages. A single variant (rs2976562) associated with monocyte SLA expression (p = 0.03) and subsequent analyses indicated that SLA downregulation following MTB stimulation associated with increased TB severity. Src Like Adaptor (SLAP-1), encoded by SLA, is highly expressed in immune cells and negatively regulates T cell receptor signaling, providing a potential mechanistic link to TB severity. CONCLUSIONS: These analyses reveal new insights into the genetics of TB severity with regulation of platelet homeostasis and vascular biology being central to consequences for active TB patients. This analysis also reveals genes that regulate inflammation can lead to differences in severity. Our findings provide an important step in improving TB patient outcomes.


Asunto(s)
Tuberculosis , Adulto , Humanos , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Inflamación/genética , Polimorfismo de Nucleótido Simple , Calidad de Vida , Tuberculosis/genética , Uganda , Sitios de Carácter Cuantitativo
2.
Am J Hum Genet ; 109(12): 2095-2100, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36459976

RESUMEN

The genotyping of millions of human samples has made it possible to evaluate variants across the human genome for their possible association with risks for numerous diseases and other traits by using genome-wide association studies (GWASs). The associations between phenotype and genotype found in GWASs make possible the construction of polygenic scores (PGSs), which aim to predict a trait or disease outcome in an individual on the basis of their genotype (in the disease case, the term polygenic risk score [PRS] is often used). PGSs have shown promise for studying the biology of complex traits and as a tool for evaluating individual disease risks in clinical settings. Although the quantity and quality of data to compute PGSs are increasing, challenges remain in the technical aspects of developing PGSs and in the ethical and social issues that might arise from their use. This ASHG Guidance emphasizes three major themes for researchers working with or interested in the application of PGSs in their own research: (1) developing diverse research cohorts; (2) fostering robustness in the development, application, and interpretation of PGSs; and (3) improving the communication of PGS results and their implications to broad audiences.


Asunto(s)
Estudio de Asociación del Genoma Completo , Herencia Multifactorial , Humanos , Herencia Multifactorial/genética , Investigación Genética , Genotipo , Fenotipo
3.
Bioinformatics ; 39(5)2023 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-37140544

RESUMEN

MOTIVATION: The identification of differentially expressed genes (DEGs) from transcriptomic datasets is a major avenue of research across diverse disciplines. However, current bioinformatic tools do not support covariance matrices in DEG modeling. Here, we introduce kimma (Kinship In Mixed Model Analysis), an open-source R package for flexible linear mixed effects modeling including covariates, weights, random effects, covariance matrices, and fit metrics. RESULTS: In simulated datasets, kimma detects DEGs with similar specificity, sensitivity, and computational time as limma unpaired and dream paired models. Unlike other software, kimma supports covariance matrices as well as fit metrics like Akaike information criterion (AIC). Utilizing genetic kinship covariance, kimma revealed that kinship impacts model fit and DEG detection in a related cohort. Thus, kimma equals or outcompetes current DEG pipelines in sensitivity, computational time, and model complexity. AVAILABILITY AND IMPLEMENTATION: Kimma is freely available on GitHub https://github.com/BIGslu/kimma with an instructional vignette at https://bigslu.github.io/kimma_vignette/kimma_vignette.html.


Asunto(s)
Perfilación de la Expresión Génica , Programas Informáticos , Humanos , RNA-Seq , Análisis de Secuencia de ARN , Modelos Lineales
4.
Community Ment Health J ; 60(3): 457-469, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-37874437

RESUMEN

The importance of community involvement for both older adults and individuals coping with mental illness is well documented. Yet, barriers to community integration for adults with mental illness such as social stigma, discrimination, and economic marginalization are often exacerbated by increased health and mobility challenges among older adults. Using photovoice, nine older adults with mental illness represented their views of community in photographs and group discussions over a six-week period. Participant themes of community life included physical spaces, valued social roles, and access to resources in the community. Themes were anchored by older adults' perceptions of historical and cultural time comparisons between 'how things used to be' and 'how things are now.' Barriers to community integration were often related to factors such as age, mobility, and resources rather than to mental health status. Program evaluation results suggest photovoice can promote self-reflection, learning, and collaboration among older adults with mental illness.


Asunto(s)
Trastornos Mentales , Fotograbar , Humanos , Anciano , Fotograbar/métodos , Estigma Social , Trastornos Mentales/psicología , Habilidades de Afrontamiento , Aprendizaje
5.
Artículo en Inglés | MEDLINE | ID: mdl-38713315

RESUMEN

Married individuals and those in committed romantic relationships generally report having better mental health outcomes than their single or divorced counterparts. However, studies of romantic relationships for adults with mental illness have often ignored rewarding aspects of romantic relationships and have focused primarily on relationship difficulties. In this study, 23 adults with serious mental illness in long-term romantic relationships described their relationship strengths and struggles in small focus group discussions. Content analysis was used to characterize themes from participant accounts. Overall, participants described deep emotional bonds with their partners, a mutual willingness to work on their relationship, and good communication skills as relationship strengths. Mental health symptoms and internalized stigma were identified as major contributors to relationship struggles. Participants spontaneously identified intentional strategies that they used to navigate mental health challenges in their relationship that included self-directed, partner-directed, and couple-directed actions. Implications of findings for research and practice are discussed.

6.
Genes Immun ; 24(3): 117-123, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37085579

RESUMEN

Resistance to M. tuberculosis, often referred to as "RSTR" in the literature, is being increasingly studied because of its potential relevance as a clinical outcome in vaccine studies. This review starts by addressing the importance of epidemiological characterization of this phenotype, and ongoing challenges in that characterization. Then, this review summarizes the extant genetic and genomic studies of this phenotype, including heritability studies, candidate gene studies, and genome-wide association studies, as well as whole transcriptome studies. Findings from recent studies that used longitudinal characterization of the RSTR phenotype are compared to those using a cross-sectional definition, and the challenges of using tuberculin skin test and interferon-gamma release assay are discussed. Finally, future directions are proposed. Since this is a rapidly evolving area of public health significance, this review will help frame future research questions and study designs.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis , Humanos , Epidemiología Molecular , Estudio de Asociación del Genoma Completo , Estudios Transversales , Tuberculosis/epidemiología , Tuberculosis/genética , Mycobacterium tuberculosis/genética , Prueba de Tuberculina
7.
Genet Epidemiol ; 46(7): 463-474, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35702824

RESUMEN

Tuberculosis and sarcoidosis are inflammatory diseases characterized by granulomas that may occur in any organ but are often found in the lung. The panoply of classical human leukocyte antigen (HLA) alleles associated with occurrence and/or severity of both diseases varies considerably across studies. This heterogeneity of results, due to variation in factors like ancestry and disease subphenotype, as well as the use of simple modeling strategies to elucidate likely complex relationships, has made conclusions about underlying commonalities difficult. Here we perform HLA association analyses in individuals of African ancestry, using a greater resolution to include subphenotypes of disease and employing more comprehensive analytical techniques. Using a novel application of nearest-neighbor feature selection to score allelic importance, we investigated HLA allele association with Mycobacterium tuberculosis exposure outcomes in the first analysis of both latent Mycobacterium tuberculosis infection and active disease compared with those who, despite long-term exposure to active index cases, have neither positive diagnostic tests nor display clinical symptoms. We also compared persistent to resolved sarcoidosis. This led to the identification of novel HLA associations and evidence of main effects and interaction effects. We found strikingly similar main effects and interaction effects at HLA-DRB1, -DQB1, and -DPB1 in those resistant to tuberculosis (either latent or active) and persistent sarcoidosis.


Asunto(s)
Mycobacterium tuberculosis , Sarcoidosis , Tuberculosis , Alelos , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Cadenas HLA-DRB1/genética , Humanos , Mycobacterium tuberculosis/genética , Sarcoidosis/genética , Tuberculosis/genética
8.
Trends Genet ; 36(12): 895-896, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32807514

RESUMEN

Data sharing is a valuable aspect of science and required by most funding bodies and journals. However, the national regulatory guidelines of many African nations do not explicitly allow for broad genetic data sharing. Given these restrictions, there is a need to reconsider these policies and propose creative solutions.


Asunto(s)
Investigación Genética/legislación & jurisprudencia , Genómica/normas , Difusión de la Información/legislación & jurisprudencia , África , Genómica/legislación & jurisprudencia , Humanos , Difusión de la Información/métodos
9.
PLoS Genet ; 16(4): e1008728, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32352966

RESUMEN

Genetic studies of both the human host and Mycobacterium tuberculosis (MTB) demonstrate independent association with tuberculosis (TB) risk. However, neither explains a large portion of disease risk or severity. Based on studies in other infectious diseases and animal models of TB, we hypothesized that the genomes of the two interact to modulate risk of developing active TB or increasing the severity of disease, when present. We examined this hypothesis in our TB household contact study in Kampala, Uganda, in which there were 3 MTB lineages of which L4-Ugandan (L4.6) is the most recent. TB severity, measured using the Bandim TBscore, was modeled as a function of host SNP genotype, MTB lineage, and their interaction, within two independent cohorts of TB cases, N = 113 and 121. No association was found between lineage and severity, but association between multiple polymorphisms in IL12B and TBscore was replicated in two independent cohorts (most significant rs3212227, combined p = 0.0006), supporting previous associations of IL12B with TB susceptibility. We also observed significant interaction between a single nucleotide polymorphism (SNP) in SLC11A1 and the L4-Ugandan lineage in both cohorts (rs17235409, meta p = 0.0002). Interestingly, the presence of the L4-Uganda lineage in the presence of the ancestral human allele associated with more severe disease. These findings demonstrate that IL12B is associated with severity of TB in addition to susceptibility, and that the association between TB severity and human genetics can be due to an interaction between genes in the two species, consistent with host-pathogen coevolution in TB.


Asunto(s)
Coevolución Biológica , Mycobacterium tuberculosis/genética , Polimorfismo de Nucleótido Simple , Tuberculosis/genética , Adolescente , Adulto , Anciano , Proteínas de Transporte de Catión/genética , Evolución Molecular , Femenino , Genoma Bacteriano , Interacciones Huésped-Patógeno , Humanos , Subunidad p40 de la Interleucina-12/genética , Masculino , Persona de Mediana Edad , Mycobacterium tuberculosis/patogenicidad , Tuberculosis/microbiología , Tuberculosis/patología
10.
J Infect Dis ; 224(4): 695-704, 2021 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-33400784

RESUMEN

BACKGROUND: Tuberculosis (TB) is the most deadly infectious disease globally and is highly prevalent in the developing world. For individuals infected with both Mycobacterium tuberculosis (Mtb) and human immunodeficiency virus (HIV), the risk of active TB is 10% or more annually. Previously, we identified in a genome-wide association study (GWAS) a region on chromosome 5 associated with resistance to TB, which included epigenetic marks that could influence gene regulation. We hypothesized that HIV-infected individuals exposed to Mtb who remain disease free carry epigenetic changes that strongly protect them from active TB. METHODS: We conducted a methylome-wide study in HIV-infected, TB-exposed cohorts from Uganda and Tanzania and integrated data from our GWAS. RESULTS: We identified 3 regions of interest that included markers that were differentially methylated between TB cases and controls with latent TB infection: chromosome 1 (RNF220, P = 4 × 10-5), chromosome 2 (between COPS8 and COL6A3, P = 2.7 × 10-5), and chromosome 5 (CEP72, P = 1.3 × 10-5). These methylation results co-localized with associated single-nucleotide polymorphisms (SNPs), methylation QTLs, and methylation × SNP interaction effects. These markers were in regions with regulatory markers for cells involved in TB immunity and/or lung. CONCLUSIONS: Epigenetic regulation is a potential biologic factor underlying resistance to TB in immunocompromised individuals that can act in conjunction with genetic variants.


Asunto(s)
Resistencia a la Enfermedad/genética , Epigénesis Genética , Epigenoma , Infecciones por VIH , Tuberculosis , Biomarcadores , Estudio de Asociación del Genoma Completo , VIH , Infecciones por VIH/complicaciones , Infecciones por VIH/genética , Humanos , Tanzanía , Tuberculosis/genética , Uganda
11.
Public Health ; 194: 67-74, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33865149

RESUMEN

OBJECTIVES: Instagram artwork about mental illness was examined to learn how artists promote awareness about mental health and mental illness. STUDY DESIGN: Mixed methods predictive and descriptive analyses were conducted on a public dataset of artwork posts from Instagram. METHODS: One thousand art images were classified by media (painting, drawing, collage, photograph, digital art, printmaking, sculpture, jewelry, or other) and style (representational, nonrepresentational, and functional). Text captions were clustered using latent semantic analysis. Predictive modeling was used to determine whether the frequency of online community response to posts (likes and comments) varied by artwork features or tagged mental health condition. RESULTS: Results suggest that artists using mental health art hashtags most often posted two-dimensional, representational art with text descriptions about emotions and personal experience. However, the minority of images of functional art objects received the most frequent number of community responses. CONCLUSIONS: Findings suggest that artists may use informational and commercial strategies to engage online communities and promote mental health awareness.


Asunto(s)
Arte , Conocimientos, Actitudes y Práctica en Salud , Promoción de la Salud/métodos , Salud Mental , Medios de Comunicación Sociales , Humanos
12.
Am J Community Psychol ; 67(3-4): 419-432, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33326631

RESUMEN

The present study examined personal disclosures about mental illness and the responses of online community members on the social media platform, Tumblr. We sampled public blog posts of 14,626 Tumblr users disclosing ten different mental health diagnoses using hashtags (e.g., #depression, #anxiety, and #anorexia). We examined the content of users' disclosures, predictors of disclosure frequency, and predictors of online community response. The content of most disclosures was related to users' emotions and cognitions about their mental health and their feelings of interpersonal loss and change over time. Content varied with users' disclosure frequency and with self-identified mental health diagnoses. Predictors of disclosure frequency included the "self effects" of writing about oneself or one's opinions, such as self-concept formation, and "reception effects" of receiving responses to one's writing. User disclosures generally increased with frequency of community response (reception effects), and the degree of this effect differed depending on the disclosed diagnosis (self effects). The responses of online community members also varied significantly across disclosed diagnoses. The implications of our findings for community research and action are discussed.


Asunto(s)
Trastornos Mentales , Medios de Comunicación Sociales , Revelación , Humanos , Trastornos Mentales/diagnóstico , Salud Mental , Autorrevelación
13.
BMC Pediatr ; 20(1): 519, 2020 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-33187500

RESUMEN

BACKGROUND: Childhood apraxia of speech (CAS) is a neurodevelopmental disorder with heterogeneous communication and other comorbid manifestations. While previous studies have characterized speech deficits associated with CAS, few studies have examined variability in reading and language and/or other developmental comorbidities. We sought to identify comorbid subgroups within CAS that could be clinically relevant as well as genetically distinctive. METHODS: In a group of 31 children with CAS and 8 controls, we performed hierarchical cluster analysis utilizing measures of articulation, vocabulary, and reading. We also conducted a chart review of the children with CAS to examine other clinical characteristics in these children and their association with subgroup membership. RESULTS: We identified 3 comorbid subgroups within CAS of varying severity. The high severity subgroup was characterized by poor reading and vocabulary, and the moderate severity subgroup by poor reading and non-word repetition but average vocabulary, compared to the mild severity subgroup. Subgroups were indistinguishable with respect to speech sound production, the hallmark of CAS, all demonstrating poor articulation. Children in the most severe subgroup were more likely to have early problems feeding (p = 0.036). CONCLUSIONS: Children with CAS may potentially be classified into comorbidity groups based on performance on vocabulary and reading measures, providing additional insight into the heterogeneity within CAS with implications for educational interventions.


Asunto(s)
Apraxias , Trastornos del Desarrollo del Lenguaje , Apraxias/diagnóstico , Apraxias/epidemiología , Niño , Humanos , Fonética , Habla , Trastornos del Habla/epidemiología
14.
PLoS Genet ; 13(6): e1006710, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28628665

RESUMEN

One in three people has been infected with Mycobacterium tuberculosis (MTB), and the risk for MTB infection in HIV-infected individuals is even higher. We hypothesized that HIV-positive individuals living in tuberculosis-endemic regions who do not get infected by Mycobacterium tuberculosis are genetically resistant. Using an "experiment of nature" design that proved successful in our previous work, we performed a genome-wide association study of tuberculin skin test positivity using 469 HIV-positive patients from prospective study cohorts of tuberculosis from Tanzania and Uganda to identify genetic loci associated with MTB infection in the context of HIV-infection. Among these individuals, 244 tested were tuberculin skin test (TST) positive either at enrollment or during the >8 year follow up, while 225 were not. We identified a genome-wide significant association between a dominant model of rs877356 and binary TST status in the combined cohort (Odds ratio = 0.2671, p = 1.22x10-8). Association was replicated with similar significance when examining TST induration as a continuous trait. The variant lies in the 5q31.1 region, 57kb downstream from IL9. Two-locus analyses of association of variants near rs877356 showed a haplotype comprised of rs877356 and an IL9 missense variant, rs2069885, had the most significant association (p = 1.59x10-12). We also replicated previously linked loci on chromosomes 2, 5, and 11. IL9 is a cytokine produced by mast cells and TH2 cells during inflammatory responses, providing a possible link between airway inflammation and protection from MTB infection. Our results indicate that studying uninfected, HIV-positive participants with extensive exposure increases the power to detect associations in complex infectious disease.


Asunto(s)
Cromosomas Humanos Par 5/genética , Estudio de Asociación del Genoma Completo , Infecciones por VIH/genética , Tuberculosis/genética , Adulto , Enfermedades Endémicas , Femenino , VIH/genética , VIH/patogenicidad , Infecciones por VIH/complicaciones , Infecciones por VIH/microbiología , Infecciones por VIH/virología , Haplotipos/genética , Humanos , Masculino , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/patogenicidad , Pruebas Cutáneas , Tanzanía , Prueba de Tuberculina , Tuberculosis/complicaciones , Tuberculosis/microbiología , Tuberculosis/virología , Uganda
15.
J Community Psychol ; 48(7): 2290-2308, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32696983

RESUMEN

Even within economically disadvantaged neighborhoods, programs fostering protective factors can shape youth outcomes. One positive youth development (PYD) program- Seeds of Change-employs teenagers in an urban neighborhood in Ohio and uses goats and community gardens to promote adolescent development. The current study used semi-structured interviews with adolescents (N = 7, ages 16-20) to conduct a case study of the program. The case study describes youth's perceptions of the neighborhood, the program, and future directions; responses were analyzed using content analysis. Youth described that Seeds of Change enacts change on multiple levels of the social ecology by emphasizing individual growth, building a social support system with peers and adults, and increasing both tangible resources and positive relationships throughout the neighborhood. Seeds of Change promotes positive socialization, increases resources, and embodies multiple elements of effective PYD programming.


Asunto(s)
Desarrollo del Adolescente , Características de la Residencia , Apoyo Social , Adolescente , Negro o Afroamericano , Femenino , Hispánicos o Latinos , Humanos , Masculino , Ohio , Pobreza , Evaluación de Programas y Proyectos de Salud , Investigación Cualitativa , Población Urbana , Adulto Joven
16.
Genes Immun ; 20(6): 473-483, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30100616

RESUMEN

Tuberculosis (TB) is a major public health burden worldwide, and more effective treatment is sorely needed. Consequently, uncovering causes of resistance to Mycobacterium tuberculosis (Mtb) infection is of special importance for vaccine design. Resistance to Mtb infection can be defined by a persistently negative tuberculin skin test (PTST-) despite living in close and sustained exposure to an active TB case. While susceptibility to Mtb is, in part, genetically determined, relatively little work has been done to uncover genetic factors underlying resistance to Mtb infection. We examined a region on chromosome 2q previously implicated in our genomewide linkage scan by a targeted, high-density association scan for genetic variants enhancing PTST- in two independent Ugandan TB household cohorts (n = 747 and 471). We found association with SNPs in neighboring genes ZEB2 and GTDC1 (peak meta p = 1.9 × 10-5) supported by both samples. Bioinformatic analysis suggests these variants may affect PTST- by regulating the histone deacetylase (HDAC) pathway, supporting previous results from transcriptomic analyses. An apparent protective effect of PTST- against body-mass wasting suggests a link between resistance to Mtb infection and healthy body composition. Our results provide insight into how humans may escape latent Mtb infection despite heavy exposure.


Asunto(s)
Cromosomas Humanos Par 2/genética , Glicosiltransferasas/genética , Tuberculosis/genética , Caja Homeótica 2 de Unión a E-Box con Dedos de Zinc/genética , Adolescente , Índice de Masa Corporal , Niño , Resistencia a la Enfermedad , Femenino , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Infecciones por VIH/complicaciones , Histona Desacetilasa 1/metabolismo , Humanos , Masculino , Polimorfismo de Nucleótido Simple , Transducción de Señal , Prueba de Tuberculina , Tuberculosis/complicaciones , Tuberculosis/prevención & control , Uganda , Adulto Joven
17.
Clin Infect Dis ; 68(10): 1705-1712, 2019 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-30165605

RESUMEN

BACKGROUND: Resistance to latent Mycobacterium tuberculosis (M.tb) infection, identified by persistently negative tuberculin skin tests (TST) and interferon-gamma release assays (IGRA), after close contact with pulmonary tuberculosis (TB) patients has not been extensively characterized. Stability of this "resistance" beyond 2 years from exposure is unknown. METHODS: 407 of 657 eligible human immunodeficiency virus (HIV)-negative adults from a TB household contact study with persistently negative TST (PTST-) or with stable latent M.tb infection (LTBI) were retraced 9.5 years (standard deviation = 3.2) later. Asymptomatic retraced contacts underwent 3 IGRAs and follow-up TST, and their M.tb infection status classified as definite/possible/probable. RESULTS: Among PTST- with a definite classification, 82.7% were concordantly TST-/ quantiferon-TB Gold- (QFT-), and 16.3% converted to TST+/QFT+ LTBI. Among original LTBI contacts, 83.6% remained LTBI, and 3.9% reverted their TST and were QFT-. Although TST and QFT concordance was high (κ = 0.78), 1.0% of PTST and 12.5% of original LTBI contacts could not be classified due to discordant TST and QFT results. Epidemiological variables did not differ between retraced PTST- and LTBI contacts. CONCLUSION: Resistance to LTBI, defined by repeatedly negative TST and IGRA, in adults who have had close contact with pulmonary TB patients living in TB-endemic areas, is a stable outcome of M.tb exposure. Repeated longitudinal measurements with 2 different immune assays and extended follow-up provide enhanced discriminatory power to identify this resister phenotype and avoid misclassification. Resisters may use immune mechanisms to control aerosolized M.tb that differ from those used by persons who develop "classic" LTBI.


Asunto(s)
Resistencia a la Enfermedad , Composición Familiar , Tuberculosis Latente/diagnóstico , Tuberculosis Pulmonar/transmisión , Adolescente , Adulto , Citocinas/sangre , Enfermedades Endémicas , Femenino , Humanos , Ensayos de Liberación de Interferón gamma , Masculino , Mycobacterium tuberculosis , Prueba de Tuberculina , Uganda , Adulto Joven
18.
Am J Hum Genet ; 98(3): 514-524, 2016 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-26942285

RESUMEN

Immunosuppression resulting from HIV infection increases the risk of progression to active tuberculosis (TB) both in individuals newly exposed to Mycobacterium tuberculosis (MTB) and in those with latent infections. We hypothesized that HIV-positive individuals who do not develop TB, despite living in areas where it is hyperendemic, provide a model of natural resistance. We performed a genome-wide association study of TB resistance by using 581 HIV-positive Ugandans and Tanzanians enrolled in prospective cohort studies of TB; 267 of these individuals developed active TB, and 314 did not. A common variant, rs4921437 at 5q33.3, was significantly associated with TB (odds ratio = 0.37, p = 2.11 × 10(-8)). This variant lies within a genomic region that includes IL12B and is embedded in an H3K27Ac histone mark. The locus also displays consistent patterns of linkage disequilibrium across African populations and has signals of strong selection in populations from equatorial Africa. Along with prior studies demonstrating that therapy with IL-12 (the cytokine encoded in part by IL12B, associated with longer survival following MTB infection in mice deficient in CD4 T cells), our results suggest that this pathway might be an excellent target for the development of new modalities for treating TB, especially for HIV-positive individuals. Our results also indicate that studying extreme disease resistance in the face of extensive exposure can increase the power to detect associations in complex infectious disease.


Asunto(s)
Sitios Genéticos , Predisposición Genética a la Enfermedad , Subunidad p40 de la Interleucina-12/genética , Tuberculosis/genética , Adolescente , Femenino , Frecuencia de los Genes , Estudio de Asociación del Genoma Completo , Infecciones por VIH/microbiología , Humanos , Subunidad p40 de la Interleucina-12/metabolismo , Desequilibrio de Ligamiento , Modelos Logísticos , Masculino , Mycobacterium tuberculosis , Estudios Prospectivos , Factores de Riesgo , Tanzanía , Tuberculosis/diagnóstico , Uganda
20.
Genet Med ; 21(7): 1541-1547, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30467403

RESUMEN

PURPOSE: While there has been a recent increase in scholarship around developing policies for the return of results from genetic sequencing, it is not clear whether these approaches are appropriate for genetic epidemiology studies. Because genetic epidemiological research increasingly utilizes genome sequencing methods, particularly in large data sets where researchers did not directly ascertain the subjects, it is important to understand researchers' perspectives on the return of results. METHODS: We conducted an online survey of members of the International Genetic Epidemiology Society to document the diversity of experiences and impressions regarding return of results. The survey contained both closed and open-ended questions. RESULTS: Among our respondents who enroll their own research participants, only 21% return secondary findings. Most respondents do not search their sequence data for clinically actionable findings not associated with their disease of interest. Many feel that genetic epidemiologists have a unique perspective on the return of results and that research studies should not follow the same procedures as clinical sequencing studies. CONCLUSION: Precision medicine initiatives that rely on both clinical and "big data" genomic research should account for variation in researcher perspectives and study design limitations when developing policies and standard practices regarding the return of results.


Asunto(s)
Investigación Genética , Hallazgos Incidentales , Epidemiología Molecular/tendencias , Investigadores , Revelación , Humanos , Análisis de Secuencia de ADN , Encuestas y Cuestionarios
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA