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Biology subjects

Samuel Scarpino

Publications and source records attributed to Samuel Scarpino.

2 recordsLinked to original sources

Analysis of clinical Bordetella pertussis isolates using whole genome sequences reveals novel genomic regions associated with recent outbreaks in the United States of America

BackgroundDespite high-levels of vaccination, whooping cough, primarily caused by Bordetella pertussis (BP), has persisted and resurged. It remains a major cause of infant death worldwide and is the most prevalent vaccine-preventable disease in developed countries. To date, most genomic studies have focused on a small subset of the BP genome, biasing our clinical understanding and public health awareness.\n\nMethodsWe performed a Genome-Wide Association Study (GWAS) on 76 U.S. BP whole genomes, including strains from recent outbreaks.\n\nResultsA GWAS of the 76 BP isolates revealed a sharp increase in genetic variation associated with the Minnesota 2012 outbreak and identified 52 variants unique to the Minnesota outbreak and 19 unique to the California and Washington outbreaks. None of the identified variants were shared between the outbreaks and the vast majority were previously uncharacterized. We further identified variation associated with pertactin negative strains and acellular vaccination.\n\nConclusionsWe identified novel genomic regions associated with recent BP outbreaks. Our results underscore the need for increased whole genome sequencing of BP isolates, which can reduce costly misdiagnosis and improve surveillance. The genes containing these variants warrant further investigation into their possible roles in BP pathogenicity and the ongoing resurgence in the U.S.

Genomics

The design and analysis of binary variable traits in common garden genetic experiments of highly fecund species to assess heritability

Many biologically important traits are binomially distributed, with their key phenotypes being presence or absence. Despite their prevalence, estimating the heritability of binomial traits presents both experimental and statistical challenges. Here we develop both an empirical and computational methodology for estimating the narrow-sense heritability of binary traits for highly fecund species. Our experimental approach controls for undesirable culturing effects, while minimizing culture numbers, increasing feasibility in the field. Our statistical approach accounts for known issues with model-selection by using a permutation test to calculate significance values and includes both fitting and power calculation methods. We illustrate our methodology by estimating the narrow-sense heritability for larval settlement, a key life-history trait, in the reef-building coral Orbicella faveolata. The experimental, statistical and computational methods, along with all of the data from this study, were deployed in the R package multiDimBio.

Evolutionary Biology