#MA30
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adoptbot.bsky.social
Meet your new feline friend, Clancy, located in East Brookfield, MA.

Learn more: https://www.petfinder.com/cat/clancy-78337971/ma/east-brookfield/second-chance-animal-shelter-inc-ma30/
Clancy is a Domestic Medium Hair and Domestic Short Hair cat, available for adoption in East Brookfield, MA.
September 21, 2025 at 5:30 PM
lesnylud.bsky.social
A jakim cudem PiS ma30% poparcia? Socjotechnika,podatność na wpływy i ot.
March 9, 2025 at 11:41 AM
adoptbot.bsky.social
Your couch companion and adventure ally awaits: Jeter, located in East Brookfield, MA.

Learn more: https://www.petfinder.com/dog/jeter-77380749/ma/east-brookfield/second-chance-animal-shelter-inc-ma30/
Jeter is a Terrier and Mixed Breed dog, available for adoption in East Brookfield, MA.
October 9, 2025 at 4:30 AM
zachhensel.bsky.social
One thing this won't do: end the "MA30" conspiracy theory.
June 30, 2026 at 10:15 AM
adoptabledogs.bsky.social
Cato 🐾
Baby male Feist mix
Adoptable from Second Chance Animal Shelter Inc. (East Brookfield, MA)

https://www.petfinder.com/dog/cato-77542048/ma/east-brookfield/second-chance-animal-shelter-inc-ma30/
Cato is a Baby Feist mix
July 30, 2025 at 11:15 AM
adoptabledogs.bsky.social
Jessie 🐾
Baby female Labrador Retriever mix
Adoptable from Second Chance Animal Shelter Inc. (East Brookfield, MA)

https://www.petfinder.com/dog/jessie-75522352/ma/east-brookfield/second-chance-animal-shelter-inc-ma30/
Jessie is a Baby Labrador Retriever mix
March 10, 2025 at 8:30 PM
scicom.bsky.social
Woher kam #COVID19? Ein neues Paper nimmt eine der meistzitierten Hypothesen zur Unterstützung eines nicht-natürlichen Ursprungs von #SARSCoV2 ins Visier und entkräftet eine konkrete Laborthese zur Furinspaltstelle (MERS-MA30). Die Autoren finden dafür keine belastbare Evidenz.🧵1/8
Significance This study formally evaluates a hypothesis that has been advanced by some scientists and public commentators in support of a nonnatural origin of SARS-CoV-2. The hypothesis proposes that the unique polybasic furin cleavage motif of SARS-CoV-2 may be technically or evolutionarily derived from a mouse-adapted laboratory strain of MERS-coronavirus (MA30). While the World Health Organization’s Scientific Advisory Group on the Origins of Novel Pathogens (SAGO) concluded that the available evidence was insufficient to support the proposed link, the underlying scientific rationale for this conclusion has not been published. We systematically assessed the evidence from genomic surveillance and conducted additional experimental studies. Together, these data do not support an evolutionary or genetic relationship. Abstract The origin of the polybasic furin cleavage site (FCS) of SARS-CoV-2 remains a central question in debates on the emergence of COVID-19. One hypothesis proposes a genetic relationship between the SARS-CoV-2 S1/S2 motif RRAR and the RRVR sequence found in the mouse-adapted MERS-CoV strain MERS-MA30. Here, we combined large-scale bioinformatic analysis with experimental virology to evaluate this scenario. Analysis of over 17 million SARS-CoV-2 genomes revealed that the S:684V substitution corresponding to RRVR occurred repeatedly but only sporadically, never became phylogenetically basal, and showed limited geographic and temporal spread. Using reverse genetics, we generated SARS-CoV-2 variants encoding RRVR and demonstrated that S:684V consistently reduced viral entry efficiency and competitive fitness in multiple cell systems, including human respiratory epithelial cultures. RRVR variants did not evolve toward RRAR but instead accumulated alternative substitutions. These findings do not support an evolutionary relationship between MERS-MA30 and the SARS-CoV-2 FCS.
July 1, 2026 at 8:21 PM
Evaluation of a proposed link between the SARS-CoV-2 furin cleavage site and mouse-adapted MERS-coronavirus MA30 www.pnas.org/doi/10.1073/...
Evaluation of a proposed link between the SARS-CoV-2 furin cleavage site and mouse-adapted MERS-coronavirus MA30 | PNAS
The origin of the polybasic furin cleavage site (FCS) of SARS-CoV-2 remains a central question in debates on the emergence of COVID-19. One hypothe...
www.pnas.org
July 7, 2026 at 12:18 AM
adoptabledogs.bsky.social
Clyde 🦮
Adult male Yorkshire Terrier mix
Adoptable from Second Chance Animal Shelter Inc. (East Brookfield, MA)

https://www.petfinder.com/dog/clyde-77598089/ma/east-brookfield/second-chance-animal-shelter-inc-ma30/
Clyde is a Adult Yorkshire Terrier mix Clyde is a Adult Yorkshire Terrier mix
August 2, 2025 at 4:30 PM
adoptabledogs.bsky.social
Aj & Romeo - Bonded Pair 🦮
Senior male Miniature Pinscher mix
Adoptable from Second Chance Animal Shelter Inc. (East Brookfield, MA)

https://www.petfinder.com/dog/aj-and-amp-romeo-bonded-pair-75614138/ma/east-brookfield/second-chance-animal-shelter-inc-ma30/
Aj & Romeo - Bonded Pair is a Senior Miniature Pinscher mix
March 15, 2025 at 4:00 AM
flodebarre.eurosky.social
We also detail, and refute, the multiple and diverse scenarios put forward to explain the FCS insertion: HIV inserts, Moderna patent, ENaC-alpha, MERS MA30.

Did we miss any? ▫️6/9
September 8, 2025 at 4:23 PM
scicom.bsky.social
Fazit:

Die Studie liefert keinen Beleg für den postulierten MA30→SARS‑CoV‑2‑Pfad. Sie zeigt vielmehr, dass dieses Labor‑Narrativ zur Furinspaltstelle weder phylogenetisch noch experimentell trägt. 7/8
July 1, 2026 at 8:21 PM
scicom.bsky.social
Experimentelle Rekonstruktionen zeigten keine stabile Entwicklung von MA30‑Typen hin zu der SARS‑CoV‑2‑Furin‑Sequenz. Damit fehlt die kombinierte genomische und experimentelle Evidenz für diese spezifische Labor‑Hypothese. 6/8
Worldwide Furin Cleavage Site (FCS) nucleotide (nt) and amino acid (AA) sequences. The FCS was extracted from 17.23 M SARS-CoV-2 sequences in the GISAID database (downloaded September 25, 2025). An 18 nt sequence containing the FCS was translated to six AAs (S681-686). (A) FCS region genome alignment showing the nt and AA sequences from the MERS-EMC (accession NC_019843.3), MERS-MA30 (MT576585.1), and the Wuhan (NC_045512.2) reference sequences for spike AA sites 682 through 685, genome sites 23,606 through 23,617 (both Left-to-Right). (B) Nucleotide distances of SARS-CoV-2 FCS sequences through March 15, 2020. The Left plot gives the distance of observed sequences to the 12 nt FCS sequence of the Wuhan strain (CGGCGGGCACGT) and the Right plot to the corresponding region in the MERS-MA30 reference (CGCCGTGTGCGC). Of the 15,993 observed genomes in this period, 15,965 (i.e., all but 28) were identical to the Wuhan sequence and at distance five from MERS-MA30. All 28 exceptions were distance one from the Wuhan sequence. Of these, four were closer, (distance 4) to the MERS-MA30 sequence, and two of these (orange dots) had a valine in the third AA position. Seventeen sequences at distance one from the Wuhan sequence were also at increased distance (six) from MERS-MA30. Uniform jitter (±0.15) was added to nucleotide distances for visual clarity. (C) Global count of FCS 6-AA sequences over time with the prevailing SARS-CoV-2 variant names appearing behind the FCS AA counts in colored rectangles. Sequences found less than 2,000 times are not shown. (D) As in C, but the Y axis shows the global percentage of all observed valine-containing AA sequences over time. (E) Periods of sustained existence of S:684V sequences. Each blue horizontal line corresponds to a S:684V-containing clade found in a ~12 M node SARS-CoV-2 phylogenetic tree (downloaded from GISAID on September 19, 2025). A golden orange horizontal region within each (blue) time period indicates the timespan during wh… The first column shows the unique 18 nucleotide (nt) sequences extracted from the GISAID database for the period through March 15, 2020, after filtering (see main text), with their standard IUPAC genetic code translations in the second column and frequency counts in the third. The MERS-MA30 FCS nt distance column shows the number of nucleotide differences between the extracted sequence in column 1 and the corresponding sequence (CGCCGTGTGCGC) in the MERS-MA30 genome. The next column has the equivalent nt distance, but to the Wuhan reference (CGGCGGGCACGT). For convenience, the third codon (i.e., sites 7 to 9) of the extracted region in the first column is given in the following column. The second last column gives the nt difference between that 3rd codon and the one from MERS-MA30 (GTG) and the final column shows the equivalent distance, but to the Wuhan reference (GCA). Code used in the production of this table is available from (10).
July 1, 2026 at 8:21 PM
merz.bsky.social
Early in the COVID pandemic I said that the furin cleavage site was the grassy knoll of SARS-CoV-2 origins truthers.

It was, is, and ever shall be.

www.pnas.org/doi/10.1073/...
Evaluation of a proposed link between the SARS-CoV-2 furin cleavage site and mouse-adapted MERS-coronavirus MA30 | PNAS
The origin of the polybasic furin cleavage site (FCS) of SARS-CoV-2 remains a central question in debates on the emergence of COVID-19. One hypothe...
www.pnas.org
July 1, 2026 at 1:46 AM
snpoehlm.bsky.social
Therefore, a fraction of the viruses that emerge in culture replace the V residue, but predominantly with G, not A.

Evaluation of a proposed link between the SARS-CoV-2 furin cleavage site and mouse-adapted MERS-coronavirus MA30 | PNAS www.pnas.org/doi/full/10....
Evaluation of a proposed link between the SARS-CoV-2 furin cleavage site and mouse-adapted MERS-coronavirus MA30 | PNAS
The origin of the polybasic furin cleavage site (FCS) of SARS-CoV-2 remains a central question in debates on the emergence of COVID-19. One hypothe...
www.pnas.org
July 1, 2026 at 9:08 AM
scicom.bsky.social
Konkret geprüft wird die Behauptung, dass die MA30‑Sequenz - ein im Labor adaptierter MERS‑Klon, der in Maus‑Passagen entstand und eine MA30‑ähnliche S1/S2‑Sequenz trägt - als realistischer Vorläufer der SARS‑CoV‑2‑FCS dienen könnte. 3/8
July 1, 2026 at 8:21 PM
inmontana.bsky.social
TWiV explains research that reveals dual activity of a phage-encoded lysin that modulates infection dynamics in a mycobacteriophage, and refutes a proposed link between the SARS-CoV-2 furin cleavage site and mouse-adapted MERS-coronavirus MA30.
July 29, 2026 at 2:42 PM
zachhensel.bsky.social
How does testing an impossible conspiracy theory justify the costs here? Were the experiments reported in this paper for some other reason as well?

www.pnas.org/doi/10.1073/...
Evaluation of a proposed link between the SARS-CoV-2 furin cleavage site and mouse-adapted MERS-coronavirus MA30 | PNAS
The origin of the polybasic furin cleavage site (FCS) of SARS-CoV-2 remains a central question in debates on the emergence of COVID-19. One hypothe...
www.pnas.org
June 30, 2026 at 10:15 AM
adoptabledogs.bsky.social
Trevor Ray - I Am at Charlton Earth Day Event 🦮
Baby male Terrier mix
Adoptable from Second Chance Animal Shelter Inc. (East Brookfield, MA)

https://www.petfinder.com/dog/trevor-ray-i-am-at-charlton-earth-day-event-76170137/ma/east-brookfield/second-chance-animal-shelter-inc-ma30/
Trevor Ray - I Am at Charlton Earth Day Event is a Baby Terrier mix
April 26, 2025 at 2:47 PM
adoptabledogs.bsky.social
Sassy & Rosie - Bonded Pair 🐕
Adult female Dachshund mix
Adoptable from Second Chance Animal Shelter Inc. (East Brookfield, MA)

https://www.petfinder.com/dog/sassy-and-amp-rosie-bonded-pair-78105013/ma/east-brookfield/second-chance-animal-shelter-inc-ma30/
Sassy & Rosie - Bonded Pair is a Adult Dachshund mix Sassy & Rosie - Bonded Pair is a Adult Dachshund mix
September 5, 2025 at 2:00 AM
pnas.org
A study fails to find a link between SARS-CoV-2, the virus that causes COVID-19, and MERS-MA30, a mouse-adapted lab strain of MERS-coronavirus. The proposed genetic link has been cited in support of a nonnatural origin for SARS-CoV-2. In PNAS: https://ow.ly/o3Gu50ZkHSf
Lab mouse. Stock image.
July 7, 2026 at 12:00 AM
adoptabledogs.bsky.social
Cloud 🐕
Young female Siberian Husky mix
Adoptable from Second Chance Animal Shelter Inc. (East Brookfield, MA)

https://www.petfinder.com/dog/cloud-75273221/ma/east-brookfield/second-chance-animal-shelter-inc-ma30/
Cloud is a Young Siberian Husky mix Cloud is a Young Siberian Husky mix Cloud is a Young Siberian Husky mix
February 21, 2025 at 5:15 PM
scicom.bsky.social
Ergebnis:
MA30‑ähnliche Sequenzen erscheinen extrem selten und nicht in phylogenetischen Positionen, die als Übergangsformen zu den frühen Pandemiestämmen infrage kämen. 5/8
July 1, 2026 at 8:21 PM