RESUMEN
The highly transmissible B.1.1.7 variant of SARS-CoV-2, first identified in the United Kingdom, has gained a foothold across the world. Using S gene target failure (SGTF) and SARS-CoV-2 genomic sequencing, we investigated the prevalence and dynamics of this variant in the United States (US), tracking it back to its early emergence. We found that, while the fraction of B.1.1.7 varied by state, the variant increased at a logistic rate with a roughly weekly doubling rate and an increased transmission of 40%-50%. We revealed several independent introductions of B.1.1.7 into the US as early as late November 2020, with community transmission spreading it to most states within months. We show that the US is on a similar trajectory as other countries where B.1.1.7 became dominant, requiring immediate and decisive action to minimize COVID-19 morbidity and mortality.
Asunto(s)
COVID-19 , Modelos Biológicos , SARS-CoV-2 , COVID-19/genética , COVID-19/mortalidad , COVID-19/transmisión , Femenino , Humanos , Masculino , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , SARS-CoV-2/patogenicidad , Estados Unidos/epidemiologíaRESUMEN
PURPOSE: Technological advances now allow for multiplex platforms to simultaneously test many genetic conditions. Typically, such platforms are validated by assaying samples with known genotypes and/or phenotypes and/or with synthetic plasmids; however, these methods have limitations and with the inclusion of rarer diseases and mutations, we can no longer rely solely on them. We used a novel genomic database to validate an expanded genetic carrier screening platform. METHODS: Our expanded carrier screening assay uses the Illumina Infinium iSelect HD Custom genotyping platform to test for 213 genetic diseases by assaying 1,663 pathogenic mutations. We leveraged two Coriell Institute biorepositories for validation: the Subcollection of Heritable Diseases and the 1000 Genomes Project. RESULTS: We measured 12,394 mutation observations in 206 samples, resulting in 246 true positives, 12,147 true negatives, 1 false positive, and no false negatives. Results demonstrated high sensitivity (99.99%) and specificity (99.99%). CONCLUSION: We successfully validated our platform with two biorepositories, demonstrating high sensitivity and specificity. The 1000 Genomes Project samples provided both positive and negative validation for mutations in genes not available through other biorepositories, expanding the depth of validated variants. We recommend including samples from the 1000 Genomes Project in the validation of future multiplex testing platforms.Genet Med advance online publication 30 July 2015Genetics in Medicine (2015); doi:10.1038/gim.2015.101.
RESUMEN
As of January of 2021, the highly transmissible B.1.1.7 variant of SARS-CoV-2, which was first identified in the United Kingdom (U.K.), has gained a strong foothold across the world. Because of the sudden and rapid rise of B.1.1.7, we investigated the prevalence and growth dynamics of this variant in the United States (U.S.), tracking it back to its early emergence and onward local transmission. We found that the RT-qPCR testing anomaly of S gene target failure (SGTF), first observed in the U.K., was a reliable proxy for B.1.1.7 detection. We sequenced 212 B.1.1.7 SARS-CoV-2 genomes collected from testing facilities in the U.S. from December 2020 to January 2021. We found that while the fraction of B.1.1.7 among SGTF samples varied by state, detection of the variant increased at a logistic rate similar to those observed elsewhere, with a doubling rate of a little over a week and an increased transmission rate of 35-45%. By performing time-aware Bayesian phylodynamic analyses, we revealed several independent introductions of B.1.1.7 into the U.S. as early as late November 2020, with onward community transmission enabling the variant to spread to at least 30 states as of January 2021. Our study shows that the U.S. is on a similar trajectory as other countries where B.1.1.7 rapidly became the dominant SARS-CoV-2 variant, requiring immediate and decisive action to minimize COVID-19 morbidity and mortality.