美国匹兹堡大学医学院W. Paul Duprex研究组发现，SARS-CoV-2突刺糖蛋白中的反复缺失可驱动抗体逃逸。这一研究成果于2021年2月3日在线发表在国际学术期刊《科学》上。

据研究人员介绍，人畜共患的大流行病，例如SARS-CoV-2，可以从动物病毒向高度易感人群的扩散。它们的后代适应了人类宿主，并逐渐逃避免疫压力。由于一种校正聚合酶，冠状病毒比其他RNA病毒更慢地获得核酸改变。

在突刺糖蛋白中，研究人员发现重复缺失克服了这种缓慢的改变率。缺失变体出现在不同的遗传和地理背景中，可以高效传播，并存在于新的谱系中，包括当前全球发现的那些。它们经常出现在重复缺失区（RDR），这可以映射到已确定的抗体表位。RDR中的缺失赋予了对中和抗体的抗性。通过改变氨基酸，缺失似乎加速了SARS-CoV-2抗原的进化，并且可能更普遍地驱动适应性进化。 

附：英文原文

Title: Recurrent deletions in the SARS-CoV-2 spike glycoprotein drive antibody escape

Author: Kevin R. McCarthy, Linda J. Rennick, Sham Nambulli, Lindsey R. Robinson-McCarthy, William G. Bain, Ghady Haidar, W. Paul Duprex

Issue&Volume: 2021/02/03

Abstract: Zoonotic pandemics, like that caused by SARS-CoV-2, can follow the spillover of animal viruses into highly susceptible human populations. Their descendants have adapted to the human host and evolved to evade immune pressure. Coronaviruses acquire substitutions more slowly than other RNA viruses, due to a proofreading polymerase. In the spike glycoprotein, we find recurrent deletions overcome this slow substitution rate. Deletion variants arise in diverse genetic and geographic backgrounds, transmit efficiently, and are present in novel lineages, including those of current global concern. They frequently occupy recurrent deletion regions (RDRs), which map to defined antibody epitopes. Deletions in RDRs confer resistance to neutralizing antibodies. By altering stretches of amino acids, deletions appear to accelerate SARS-CoV-2 antigenic evolution and may, more generally, drive adaptive evolution.

DOI: 10.1126/science.abf6950

Source: https://science.sciencemag.org/content/early/2021/02/02/science.abf6950