There are a lot of official news and poor-quality academic articles from end of last Dec show that no evidence about wild animals in Huanan seafood market as intermediate host for 2019 nCoV (which can be explained in a detail way later). Hence, one hypothesis of lab-made 2019 nCoV is recombined with SARS RBD of S protein (to human ACE2 gene), based on ZS bat-CoV (esp. MG772933.1), going through in vitro and in vivo adaptation and amplification in a limited range in the lab, generated an ideal strain (2019 nCoV) with effective RBD, while the other comparable conserved sequence did not change much, or even without any change (E protein). Since stock virus kept in culture media at -80 ℃, slowly thaw it on ice could help the virus released in the environment better.
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