Part of a series on the |
COVID-19 pandemic |
---|
|
COVID-19 portal |
The Mu variant, also known as lineage B.1.621 or VUI-21JUL-1, is one of the variants of SARS-CoV-2, the virus that causes COVID-19. It was first detected in Colombia in January 2021 and was designated by the WHO as a variant of interest on August 30, 2021. [1] The WHO said the variant has mutations that indicate a risk of resistance to the current vaccines and stressed that further studies were needed to better understand it. [2] [3] Outbreaks of the Mu variant were reported in South America and Europe. [4] The B.1.621 lineage has a sublineage, labeled B.1.621.1 under the PANGO nomenclature, which has already been detected in more than 20 countries worldwide. [5]
Under the simplified naming scheme proposed by the World Health Organization, B.1.621 was labeled "Mu variant", and was considered a variant of interest (VOI), but not a variant of concern. [1]
In January 2021, the lineage was first documented in Colombia and was named as lineage B.1.621. [6]
On July 1, 2021, Public Health England (PHE) named lineage B.1.621 VUI-21JUL-1. [7]
On August 30, 2021, the World Health Organization (WHO) named lineage B.1.621 Mu variant. [1]
The Mu genome has a total number of 21 mutations, including 9 amino acid mutations, all of which are in the virus's spike protein code: T95I, Y144S, Y145N, R346K, E484K or the escape mutation, N501Y, D614G, P681H, and D950N. [8] It has an insertion of one amino acid at position 144/145 of the spike protein, giving a total mutation YY144–145TSN. That mutation is conventionally notated as Y144S and Y145N because insertions would break a lot of comparison tools. It also features a frame-shift deletion of four nucleotides in ORF3a that generates a stop codon two amino acids. The mutation is labeled as V256I, N257Q, and P258*. The list of defining mutations are: S: T95I, Y144S, Y145N, R346K, E484K, N501Y, D614G, P681H, and D950N; ORF1a: T1055A, T1538I, T3255I, Q3729R; ORF1b: P314L, P1342S; N: T205I, ORF3a: Q57H, V256I, N257Q, P258*; ORF8: T11K, P38S, S67F. [9] Mutations in viruses are not new. All viruses, including SARS-CoV-2, undergo change over time. Most of these changes are inconsequential, but some can alter properties to make these viruses more virulent or escape the treatment or vaccines. [4]
On August 31, 2021, the WHO released an update which stated that the "Mu variant has a constellation of mutations that indicate potential properties of immune escape", noting that preliminary studies showed some signs of this but that "this needs to be confirmed by further studies." [10]
One such study conducted in a lab in Rome tested the effectiveness of sera collected from recipients of the BioNTech-Pfizer vaccine against the Mu variant, and found that "neutralization of SARS-CoV-2 B.1.621 lineage was robust", albeit at a lower level than that observed against the B.1 variant. [11]
Gene | Amino acid |
---|---|
ORF1a | T1055A |
T1538I | |
T3255I | |
Q3729R | |
ORF1b | P314L |
P1342S | |
S | T95I |
Y144S | |
Y145N | |
R346K | |
E484K | |
N501Y | |
D614G | |
P681H | |
D950N | |
ORF3a | Q57H |
del257/257 | |
ORF8 | T11K |
P38S | |
S67F | |
N | T205I |
August 6:
August 30:
September 2:
September 3:
September 4:
September 7:
September 8:
September 9:
September 16:
September 18:
Country | GISAID [36] | outbreak.info [8] | other sources |
---|---|---|---|
USA | 5,550 | 6,550 | |
Colombia | 3,995 | 4,974 | |
Chile | 850 | 958 | |
Spain | 665 | 690 | |
Ecuador | 352 | 447 | |
Mexico | 345 | 435 | |
Peru | 240 | 276 | 86 [22] |
Canada | 142 | 162 | |
Dominican Republic | 115 | 118 | |
Aruba | 94 | 94 | |
Italy | 82 | 85 | |
Netherlands | 76 | 76 | 46 [37] |
Costa Rica | 73 | 74 | |
United Kingdom | 71 | 67 | 59 [38] |
Puerto Rico | 57 | 57 | |
Belgium | 51 | 51 | |
Austria | 49 | 49 | |
Switzerland | 48 | 48 | |
Argentina | 41 | 42 | 1 [30] |
British Virgin Islands | 41 | 41 | |
Jamaica | 33 | 33 | 26 [27] |
France | 29 | 28 | |
Mongolia | 20 | 20 | |
Portugal | 20 | 25 | |
Curacao | 19 | 20 | |
Brazil | 17 | 21 | 12 [31] [32] [33] [34] |
Panama | 16 | 16 | |
Germany | 15 | 16 | |
Venezuela | 15 | 15 | |
Denmark | 11 | 12 | |
Bolivia | 10 | 10 | |
Bonaire | 8 | 10 | |
Poland | 8 | 8 | |
Finland | 5 | 5 | 1 [35] |
Haiti | 5 | 6 | |
Japan | 5 | 5 | 2 [14] |
U.S. Virgin Islands | 5 | 5 | 1 [24] |
Ireland | 4 | 4 | 4 [21] |
Slovakia | 4 | 4 | |
Sweden | 4 | 4 | |
Guatemala | 3 | 4 | 2 [16] |
Hong Kong | 3 | 3 | 3 [19] |
Luxembourg | 3 | 3 | |
Cayman Islands | 2 | 3 | |
Israel | 2 | 2 | |
Saint Vincent and the Grenadines | 2 | 3 | 5 [26] |
Sint Maarten | 2 | 3 | |
Turkey | 2 | 2 | 2 [25] |
Barbados | 1 | 1 | |
Czech Republic | 1 | 1 | |
Gibraltar | 1 | 1 | |
Liechtenstein | 1 | 1 | |
Lithuania | 1 | 1 | |
Malta | 1 | 1 | |
Morocco | 1 | 1 | |
South Korea | 1 | 1 | 3 [20] |
Turks and Caicos Islands | 1 | 1 | |
Romania | 1 | 1 | |
Greece | 1 | 1 | 6 [18] |
Taiwan | 1 | 1 | 1 [15] |
Total | 12,952 | 15,090 | 260 |
Part of a series on the |
COVID-19 pandemic |
---|
|
COVID-19 portal |
The Mu variant, also known as lineage B.1.621 or VUI-21JUL-1, is one of the variants of SARS-CoV-2, the virus that causes COVID-19. It was first detected in Colombia in January 2021 and was designated by the WHO as a variant of interest on August 30, 2021. [1] The WHO said the variant has mutations that indicate a risk of resistance to the current vaccines and stressed that further studies were needed to better understand it. [2] [3] Outbreaks of the Mu variant were reported in South America and Europe. [4] The B.1.621 lineage has a sublineage, labeled B.1.621.1 under the PANGO nomenclature, which has already been detected in more than 20 countries worldwide. [5]
Under the simplified naming scheme proposed by the World Health Organization, B.1.621 was labeled "Mu variant", and was considered a variant of interest (VOI), but not a variant of concern. [1]
In January 2021, the lineage was first documented in Colombia and was named as lineage B.1.621. [6]
On July 1, 2021, Public Health England (PHE) named lineage B.1.621 VUI-21JUL-1. [7]
On August 30, 2021, the World Health Organization (WHO) named lineage B.1.621 Mu variant. [1]
The Mu genome has a total number of 21 mutations, including 9 amino acid mutations, all of which are in the virus's spike protein code: T95I, Y144S, Y145N, R346K, E484K or the escape mutation, N501Y, D614G, P681H, and D950N. [8] It has an insertion of one amino acid at position 144/145 of the spike protein, giving a total mutation YY144–145TSN. That mutation is conventionally notated as Y144S and Y145N because insertions would break a lot of comparison tools. It also features a frame-shift deletion of four nucleotides in ORF3a that generates a stop codon two amino acids. The mutation is labeled as V256I, N257Q, and P258*. The list of defining mutations are: S: T95I, Y144S, Y145N, R346K, E484K, N501Y, D614G, P681H, and D950N; ORF1a: T1055A, T1538I, T3255I, Q3729R; ORF1b: P314L, P1342S; N: T205I, ORF3a: Q57H, V256I, N257Q, P258*; ORF8: T11K, P38S, S67F. [9] Mutations in viruses are not new. All viruses, including SARS-CoV-2, undergo change over time. Most of these changes are inconsequential, but some can alter properties to make these viruses more virulent or escape the treatment or vaccines. [4]
On August 31, 2021, the WHO released an update which stated that the "Mu variant has a constellation of mutations that indicate potential properties of immune escape", noting that preliminary studies showed some signs of this but that "this needs to be confirmed by further studies." [10]
One such study conducted in a lab in Rome tested the effectiveness of sera collected from recipients of the BioNTech-Pfizer vaccine against the Mu variant, and found that "neutralization of SARS-CoV-2 B.1.621 lineage was robust", albeit at a lower level than that observed against the B.1 variant. [11]
Gene | Amino acid |
---|---|
ORF1a | T1055A |
T1538I | |
T3255I | |
Q3729R | |
ORF1b | P314L |
P1342S | |
S | T95I |
Y144S | |
Y145N | |
R346K | |
E484K | |
N501Y | |
D614G | |
P681H | |
D950N | |
ORF3a | Q57H |
del257/257 | |
ORF8 | T11K |
P38S | |
S67F | |
N | T205I |
August 6:
August 30:
September 2:
September 3:
September 4:
September 7:
September 8:
September 9:
September 16:
September 18:
Country | GISAID [36] | outbreak.info [8] | other sources |
---|---|---|---|
USA | 5,550 | 6,550 | |
Colombia | 3,995 | 4,974 | |
Chile | 850 | 958 | |
Spain | 665 | 690 | |
Ecuador | 352 | 447 | |
Mexico | 345 | 435 | |
Peru | 240 | 276 | 86 [22] |
Canada | 142 | 162 | |
Dominican Republic | 115 | 118 | |
Aruba | 94 | 94 | |
Italy | 82 | 85 | |
Netherlands | 76 | 76 | 46 [37] |
Costa Rica | 73 | 74 | |
United Kingdom | 71 | 67 | 59 [38] |
Puerto Rico | 57 | 57 | |
Belgium | 51 | 51 | |
Austria | 49 | 49 | |
Switzerland | 48 | 48 | |
Argentina | 41 | 42 | 1 [30] |
British Virgin Islands | 41 | 41 | |
Jamaica | 33 | 33 | 26 [27] |
France | 29 | 28 | |
Mongolia | 20 | 20 | |
Portugal | 20 | 25 | |
Curacao | 19 | 20 | |
Brazil | 17 | 21 | 12 [31] [32] [33] [34] |
Panama | 16 | 16 | |
Germany | 15 | 16 | |
Venezuela | 15 | 15 | |
Denmark | 11 | 12 | |
Bolivia | 10 | 10 | |
Bonaire | 8 | 10 | |
Poland | 8 | 8 | |
Finland | 5 | 5 | 1 [35] |
Haiti | 5 | 6 | |
Japan | 5 | 5 | 2 [14] |
U.S. Virgin Islands | 5 | 5 | 1 [24] |
Ireland | 4 | 4 | 4 [21] |
Slovakia | 4 | 4 | |
Sweden | 4 | 4 | |
Guatemala | 3 | 4 | 2 [16] |
Hong Kong | 3 | 3 | 3 [19] |
Luxembourg | 3 | 3 | |
Cayman Islands | 2 | 3 | |
Israel | 2 | 2 | |
Saint Vincent and the Grenadines | 2 | 3 | 5 [26] |
Sint Maarten | 2 | 3 | |
Turkey | 2 | 2 | 2 [25] |
Barbados | 1 | 1 | |
Czech Republic | 1 | 1 | |
Gibraltar | 1 | 1 | |
Liechtenstein | 1 | 1 | |
Lithuania | 1 | 1 | |
Malta | 1 | 1 | |
Morocco | 1 | 1 | |
South Korea | 1 | 1 | 3 [20] |
Turks and Caicos Islands | 1 | 1 | |
Romania | 1 | 1 | |
Greece | 1 | 1 | 6 [18] |
Taiwan | 1 | 1 | 1 [15] |
Total | 12,952 | 15,090 | 260 |