Background: A birth and death process is frequently used for modeling the size of a gene family that may vary along the branches of a phylogenetic tree. Under the birth and death model, maximum likelihood methods have been developed to estimate the birth and death rate and the sizes of ancient gene families (numbers of gene copies at the internodes of the phylogenetic tree). This paper aims to provide a Bayesian approach for estimating parameters in the birth and death model.
Results: We develop a Bayesian approach for estimating the birth and death rate and other parameters in the birth and death model. In addition, a Bayesian hypothesis test is developed to identify the gene families that are unlikely under the birth and death process. Simulation results suggest that the Bayesian estimate is more accurate than the maximum likelihood estimate of the birth and death rate. The Bayesian approach was applied to a real dataset of 3517 gene families across genomes of five yeast species. The results indicate that the Bayesian model assuming a constant birth and death rate among branches of the phylogenetic tree cannot adequately explain the observed pattern of the sizes of gene families across species. The yeast dataset was thus analyzed with a Bayesian heterogeneous rate model that allows the birth and death rate to vary among the branches of the tree. The unlikely gene families identified by the Bayesian heterogeneous rate model are different from those given by the maximum likelihood method.
Conclusions: Compared to the maximum likelihood method, the Bayesian approach can produce more accurate estimates of the parameters in the birth and death model. In addition, the Bayesian hypothesis test is able to identify unlikely gene families based on Bayesian posterior p-values. As a powerful statistical technique, the Bayesian approach can effectively extract information from gene family data and thereby provide useful information regarding the evolutionary process of gene families across genomes.
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http://dx.doi.org/10.1186/1471-2105-12-426 | DOI Listing |
BMJ Open Qual
January 2025
Universitas Gadjah Mada, Yogyakarta, Daerah Istimewa Yogyakarta, Indonesia.
Background: The neonatal mortality rate in Papua Province of Indonesia is unacceptably high. To address the issue, the Ministry of Health and UNICEF Indonesia initiated a hospital mentoring programme from 2014 to 2016 to improve the quality of care and health workers' capacity to provide neonatal care. This study aimed to assess the impact of hospital mentoring on neonatal mortality.
View Article and Find Full Text PDFIntroduction: Screening for congenital adrenal hyperplasia through the measurement of 17-hydroxyprogesterone on the neonatal blood spot aims to: a) prevent neonatal deaths; b) allow earlier identification and thereby decrease the severity of the initial salt-wasting episode; and c) shorten the time during which a severely virilized genetic female newborn may be assigned the male sex. It is now practiced in the majority of high-income countries, although the positive predictive value of the test is very low in infants born preterm, who seem to be infrequently affected. In almost all low- and middle-income countries, it has not yet been implemented.
View Article and Find Full Text PDFAm J Forensic Med Pathol
November 2024
Connecticut Office of the Chief Medical Examiner, Farmington, CT.
Stillborn and perinatal deaths may be referred to medical examiners and coroners for investigation and determination of cause and/or manner of death. One of the key questions is determining a live birth from a stillbirth. We surveyed 147 forensic pathologists to assess their investigative practices for these deaths and for their ability to diagnose a live birth and a stillbirth.
View Article and Find Full Text PDFEur J Public Health
January 2025
Department of Health, Behavior, and Society, Faculty of Public Health, Institute of Health, Jimma University, Jimma, Ethiopia.
Maternal mortality remains a critical global health challenge, with 95% of deaths occurring in low-income countries. While progress was made from 2000 to 2015, regions such as Ethiopia continue to experience high maternal mortality rates, impeding the achievement of the sustainable development goal to reduce maternal deaths to 70 per 100 000 live births by 2030. This study evaluated the effectiveness of a Social and Behavior Change Communication (SBCC) intervention to improve maternal health behaviors.
View Article and Find Full Text PDFACS Infect Dis
January 2025
Department of Microbiology, Genetics, and Immunology, Michigan State University, East Lansing, Michigan 48824, United States.
Group B (GBS) is a major cause of fetal and neonatal mortality worldwide. Many of the adverse effects of invasive GBS are associated with inflammation; therefore, understanding bacterial factors that promote inflammation is of critical importance. Membrane vesicles (MVs), which are produced by many bacteria, may modulate host inflammatory responses.
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