SARS-CoV-2 Epidemiology on a Public University Campus in Washington State.

BACKGROUND: We aimed to evaluate a testing program to facilitate control of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission at a large university and measure spread in the university community using viral genome sequencing. METHODS: Our prospective longitudinal study used remote contactless enrollment, daily mobile symptom and exposure tracking, and self-swab sample collection. Individuals were tested if the participant was exposed to a known SARS-CoV-2-infected person, developed new symptoms, or reported high-risk behavior (such as attending an indoor gathering without masking or social distancing), if a member of a group experiencing an outbreak, or at enrollment. Study participants included students, staff, and faculty at an urban public university during the Autumn quarter of 2020. RESULTS: We enrolled 16 476 individuals, performed 29 783 SARS-CoV-2 tests, and detected 236 infections. Seventy-five percent of positive cases reported at least 1 of the following: symptoms (60.8%), exposure (34.7%), or high-risk behaviors (21.5%). Greek community affiliation was the strongest risk factor for testing positive, and molecular epidemiology results suggest that specific large gatherings were responsible for several outbreaks. CONCLUSIONS: A testing program focused on individuals with symptoms and unvaccinated persons who participate in large campus gatherings may be effective as part of a comprehensive university-wide mitigation strategy to control the spread of SARS-CoV-2.

Simultaneous digital quantification and fluorescence-based size characterization of massively parallel sequencing libraries.

Due to the high cost of failed runs and suboptimal data yields, quantification and determination of fragment size range are crucial steps in the library preparation process for massively parallel sequencing (or next-generation sequencing). Current library quality control methods commonly involve quantification using real-time quantitative PCR and size determination using gel or capillary electrophoresis. These methods are laborious and subject to a number of significant limitations that can make library calibration unreliable. Herein, we propose and test an alternative method for quality control of sequencing libraries using droplet digital PCR (ddPCR). By exploiting a correlation we have discovered between droplet fluorescence and amplicon size, we achieve the joint quantification and size determination of target DNA with a single ddPCR assay. We demonstrate the accuracy and precision of applying this method to the preparation of sequencing libraries.

The Centers for Mendelian Genomics: a new large-scale initiative to identify the genes underlying rare Mendelian conditions.

Next generation exome sequencing (ES) and whole genome sequencing (WGS) are new powerful tools for discovering the gene(s) that underlie Mendelian disorders. To accelerate these discoveries, the National Institutes of Health has established three Centers for Mendelian Genomics (CMGs): the Center for Mendelian Genomics at the University of Washington; the Center for Mendelian Genomics at Yale University; and the Baylor-Johns Hopkins Center for Mendelian Genomics at Baylor College of Medicine and Johns Hopkins University. The CMGs will provide ES/WGS and extensive analysis expertise at no cost to collaborating investigators where the causal gene(s) for a Mendelian phenotype has yet to be uncovered. Over the next few years and in collaboration with the global human genetics community, the CMGs hope to facilitate the identification of the genes underlying a very large fraction of all Mendelian disorders; see http://mendelian.org.

Overview of DNA sequencing strategies.

Efficient and cost-effective DNA sequencing technologies are critical to the progress of molecular biology. This overview of DNA sequencing strategies provides a high-level review of seven distinct approaches to DNA sequencing: (a) dideoxy sequencing; (b) solid phase sequencing; (c) sequencing-by-hybridization; (d) mass spectrometry; (e) cyclic array sequencing; (f) microelectrophoresis; and (g) nanopore sequencing. Other platforms currently in development are also briefly described. The primary focus here is on Sanger dideoxy sequencing, which has been the dominant technology since 1977, and on cyclic array strategies, for which several competitive implementations have been developed since 2005. Because the field of DNA sequencing is changing rapidly, this unit represents a snapshot as of September, 2011.

Overview of DNA sequencing strategies.

Efficient and cost-effective DNA sequencing technologies have been, and may continue to be, critical to the progress of molecular biology. This overview of DNA sequencing strategies provides a high-level review of six distinct approaches to DNA sequencing: (a) dideoxy sequencing; (b) cyclic array sequencing; (c) sequencing-by-hybridization; (d) microelectrophoresis; (e) mass spectrometry; and (f) nanopore sequencing. The primary focus is on dideoxy sequencing, which has been the dominant technology since 1977, and on cyclic array strategies, for which several competitive implementations have been developed since 2005. Because the field of DNA sequencing is changing rapidly, this unit represents a snapshot of this particular moment.