The SARS-CoV-2 Omicron Variant

On 26 November 2021, the WHO designated the SARS-CoV-2 variant B.1.1.529 to be the fifth Variant of Concern (VOC) and assigned it the name “Omicron”. Of the more than 50 mutations in its genome, at least 32 are in the spike protein with fifteen point mutations in the RBD (Figure 1), including several found in other VOCs linked to increased transmissibility and immune evasion. Like other VOCs, mutations are also found in Omicron’s nucleocapsid protein (Figure 2). Omicron is widely distributed and is outcompeting Delta. Though it appears to cause more mild disease, it nevertheless has driven increased hospitalizations.

Figure 1. Spike mutation sites found in Omicron are A67V, Δ69-70, T95I, G142D/Δ143-145, Δ211/L212I, ins214EPE, G339D, S371L, S373P, S375F, K417N, N440K, G446S, S477N, T478K, E484A, Q493K, G496S, Q498R, N501Y, Y505H, T547K, D614G, H655Y, N679K, P681H, N764K, D796Y, N856K, Q954H, N969K, L981F.

Figure 2. Nucleocapsid protein mutation sites found in Omicron are P13L, Δ31-33, R203K, G204R, and in Delta are D63G, R203M, G215C, D377Y.

GeneTex has a wide range of recombinant antibody and protein reagents for Omicron research. Notably, nucleocapsid antibodies whose immunogens do not contain any Omicron mutation sites are shown in Figure 2.

Spike RBD Protein, B.1.1.529 / Omicron variant, His tag (GTX136716-pro)

Spike RBD Protein, BA.2 / Omicron variant, His tag (GTX136905-pro)

Spike RBD antibody [HL257] (GTX635692)

Spike RBD antibody [HL1014] (GTX635807)

Lateral Flow Assay (Recommended Nucleocapsid Antibody Pairs)

Antibody Pair   Product Name Clonality EC50 Cat. No. Pair I    Nucleocapsid antibody [HL5511] Rb recAb 14 pM GTX635689   Nucleocapsid antibody [HL448] Rb recAb 11 pM GTX635686 Pair II   Nucleocapsid antibody [HL5410] Rb recAb 9 pM GTX635685   Nucleocapsid antibody [HL455] Rb recAb 6 pM GTX635688

Reagents that detect Omicron

Product Name Applications Cat. No.   Spike RBD Protein Sandwich ELISA Kit ELISA|Sandwich ELISA GTX536267   Spike RBD antibody [HL1014] ICC/IF|ELISA|Sandwich ELISA GTX635807   Spike RBD antibody [HL1003] ICC/IF|ELISA|Neutralizing/Inhibition|Sandwich ELISA GTX635792   Spike RBD antibody [HL1003] (HRP) ELISA|Sandwich ELISA GTX635792-01   Spike RBD antibody [HL257] WB|ICC/IF|IHC-P|ELISA|IHC-P (cell pellet) GTX635692 Spike S2 antibody [HL237] WB|ICC/IF|ELISA|Sandwich ELISA|IHC-P (cell pellet) GTX635693   Spike antibody [1A9] WB|ICC/IF|IHC-P|FACS|IP|ELISA|Sandwich ELISA|IHC-P (cell pellet)|EM GTX632604    Nucleocapsid antibody [HL5511] WB|ICC/IF|ELISA|Lateral Flow|Sandwich ELISA|IHC-P (cell pellet) GTX635689    Nucleocapsid antibody [HL5410] WB|ICC/IF|ELISA|Lateral Flow|Sandwich ELISA|IHC-P (cell pellet) GTX635685   Nucleocapsid antibody [HL448] WB|ICC/IF|IHC-P|ELISA|Lateral Flow|Sandwich ELISA|IHC-P (cell pellet) GTX635686    Nucleocapsid antibody [HL455] WB|ICC/IF|ELISA|Lateral Flow|Sandwich ELISA|IHC-P (cell pellet) GTX635688   Nucleocapsid antibody [HL448] (HRP) WB|ELISA|Sandwich ELISA GTX635686-01