SARS-CoV2 is the virus which causes COVID-19, the form of coronavirus which is now a global pandemic. The gene ACE2 is involved when SARS-CoV2 infection occurs and the eye is an important possible place of entry for the virus to get into the body. It is thought that the virus enters the eye through ACE2, but this remains unclear. We will look at gene expression in eye tissue to identify whether ACE2 is important in the eye and generate a picture of biomarkers of the eye which may predict disease severity. This will help in understanding the first steps in the mechanism of infection and potential targets for therapies. We will be using excess surgical tissue from the eyes of non COVID-19 patients undergoing surgery for other reasons.