Alliance for Pandemic Preparedness

February 5, 2020

Genomic variance of the 2019-nCoV coronavirus



  • Ceraolo and Giorgi construct an expansive phylogenetic tree of representative coronaviridae. They confirm a >99% match among sequenced 2019-nCov isolates; and a 96.2% match between 2019-nCoV and the most closely-related bat coronavirus. While 2019-nCoV sequences were fairly homogenous, at least two hyper-variable genomic areas were identified (ORF 1ab, silent; ORF8, serine/leucine variation).
  • They also assessed protein homology, finding again considerable similarity between 2019-nCoV and one of the bat CoVs. Envelope, membrane, and nucleocapsid proteins were generally highly conserved. 

Ceraolo C and Giorgi FM (Feb 4, 2020). Genomic variance of the 2019-nCoV coronavirus. Pre-Print downloaded on 5 Feb, 2020 from,