Analysis of SARS-COV2 spike protein variants among Iraqi isolates

Gene Rep. 2022 Mar:26:101420. doi: 10.1016/j.genrep.2021.101420. Epub 2021 Nov 4.

Abstract

The ongoing pandemic of COVID-19 caused by the SARS-COV2 virus has triggered millions of deaths around the globe. Emerging several variants of the virus with increased transmissibility, the severity of disease, and the ability of the virus to escape from the immune system has a cause for concerns. Here, we compared the spike protein sequence of 91 human SARS CoV2 strains of Iraq to the first reported sequence of SARS-CoV2 isolate from Wuhan Hu-1/China. The strains were isolated between June 2020 and March 2021. Twenty-two distinct mutations were identified within the spike protein regions which were: L5F, L18F, T19R, S151T, G181A, A222V, A348S, L452 (Q or M), T478K, N501Y, A520S, A522V, A570D, S605A, D614G, Q675H, N679K, P681H, T716I, S982A, A1020S, D1118H. The most frequently mutations occurred at the D614G (87/91), followed by S982A (50/91), and A570D (48/91), respectively. In addition, a distinct shift was observed in the type of SARS-COV2 variants present in 2020 compared to 2021 isolates. In 2020, B.1.428.1 lineage was appeared to be a dominant variant (85%). However, the diversity of the variants increased in 2021, and the majority (73%) of the isolated were appeared to belong to B.1.1.7 lineage (VOC/alpha variants). To our knowledge, this is the first major genome analysis of SARS-CoV2 in Iraq. The data from this research could provide insights into SARS-CoV2 evolution, and can be potentially used to recognize the effective vaccine against the disease.

Keywords: ACE2, Angiotensin-Converting Enzyme 2; CP, Cytoplasmic Peptide; Covid-19; FP, Fusion peptide; GISAID, Global Initiative on Sharing All Influenza Data; HR1, Heptad Repeat 1; HR2, Heptad Repeat 2; Iraq; Mutation; NTD, N-terminal domain; PDB, Protein Data Bank; RBD, Receptor-Binding Domain; Receptor binding domain; SARS-COV2; SARS-CoV2, Severe acute respiratory syndrome coronavirus 2; SP, Signal Peptide; Spike protein; TM, Transmembrane Domain; VOC, Virus of Concern.