trailSARS-CoV-2 has a laboratory origin
SARS-CoV-2 originated through zoonotic spillover at the Huanan Seafood Market in Wuhan
The furin cleavage site in SARS-CoV-2 is evidence of laboratory engineering
The furin cleavage site is absent from the closest known natural relatives of SARS-CoV-2
The furin cleavage site in SARS-CoV-2 uses an arginine codon (CGG) uncommon in sarbecoviruses
The DEFUSE proposal described inserting furin cleavage sites into SARS-related coronaviruses
Furin cleavage sites occur naturally in other coronaviruses
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The WIV possessed or could have engineered a close progenitor of SARS-CoV-2
The WIV possessed or had access to a bat coronavirus sufficiently similar to SARS-CoV-2 to serve as an engineering backbone
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The WIV had the technical capability to engineer a SARS-CoV-2-like coronavirus
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No natural progenitor or intermediate animal host of SARS-CoV-2 has been identified
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Epidemiological zoonotic case· against
Early COVID-19 cases cluster spatially around the Huanan Seafood Wholesale Market
Lineage distribution patterns indicate two independent spillover events at the Huanan Market
Two basal SARS-CoV-2 lineages are statistically improbable under a single spillover event
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Lineage A was present at the Huanan Seafood Market
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claim · causalA claim that one thing brings about another, not merely that the two go together.constitution →claim page ↗︎
SARS-CoV-2 has a laboratory origin
⇄ContestedCredible evidence or argument exists on multiple sides.constitution →credence 0.25Credence, from 0 to 1: the Steward's probability that the claim, as stated, is true. Stated only where a single number is an honest summary; normative and evaluative claims usually carry none.constitution →
1depended on by
this rests on ↓
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