I'm agnostic on its various hypotheses about mechanisms of origin of furin-cleavage sites, but the part of this paper that suggests furin-cleavage site might be present in two of these SARSr-CoVs as a minor variant is embarrassingly bad science that shouldn't be amplified. (1/n)

Here is Table 1 of pre-print (https://t.co/7fQsreN77n) that shows data related to this claim. The mutations in question are present at 0.004% and 0.006%, corresponding to 6 or 7 Illumina reads out of >100,000 total. (2/n)
There are good deep-sequencing studies of CoVs, eg by @katrina_lythgoe (https://t.co/joX4kCqOEh), @LauringLab (https://t.co/TisAPvkCVp) & @KATarinambraun @tcfriedrich @trvrb @LouiseHMoncla (https://t.co/08EhfVAAL1). These studies find you can call variants to 2-3% frequency (3/n)
Table 1 of this pre-print is reporting "mutations" that introduce a furin-cleavage site at frequencies of 0.004% to 0.006%, which is orders of magnitude lower than what good studies have rigorously defined as a reasonable threshold (2-3%) to call mutations. (4/n)
As anybody who has ever analyzed viral or cancer deep sequencing knows, it's simply impossible to use standard Illumina sequencing to identify mutations at even 0.4% or 0.04%, let alone 0.004%. It's actually surprising when a given sequencing error isn't present at ~0.01%. (5/n)
So what this study should say is: we found some bat SARS-related CoVs that are just one or a few mutations away from having a furin cleavage site, but none of them actually have a furin cleavage site even as a minor variant. (6/n)
Above point also currently caveated, since pre-print only shows 10-codon chunk of BB99-04 & no sequence of BB89-98. This region of spike is subject to substantial alignment uncertainty, so withhold judgment until enough of the sequences released to support the alignments (7/n)

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1

From today, we will memorize the names of 27 Nakshatras in Vedic Jyotish to never forget in life.

I will write 4 names. Repeat them in SAME sequence twice in morning, noon, evening. Each day, revise new names + recall all previously learnt names.

Pls RT if you are in.

2

Today's Nakshatras are:-

1. Ashwini - अश्विनी

2. Bharani - भरणी

3. Krittika - कृत्तिका

4. Rohini - रोहिणी

Ashwini - अश्विनी is the FIRST Nakshatra.

Repeat these names TWICE now, tomorrow morning, noon and evening. Like this tweet if you have revised 8 times as told.

3

Today's Nakshatras are:-

5. Mrigashira - मृगशिरा

6. Ardra - आर्द्रा

7. Punarvasu - पुनर्वसु

8. Pushya - पुष्य

First recall previously learnt Nakshatras twice. Then recite these TWICE now, tomorrow morning, noon & evening in SAME order. Like this tweet only after doing so.

4

Today's Nakshatras are:-

9. Ashlesha - अश्लेषा

10. Magha - मघा

11. Purvaphalguni - पूर्वाफाल्गुनी

12. Uttaraphalguni - उत्तराफाल्गुनी

Purva means that comes before (P se Purva, P se pehele), and Uttara comes later.

Read next tweet too.

5

Purva, Uttara prefixes come in other Nakshatras too. Purva= pehele wala. Remember.

First recall previously learnt 8 Nakshatras twice. Then recite those in Tweet #4 TWICE now, tomorrow morning, noon & evening in SAME order. Like this tweet if you have read Tweets #4 & 5, both.