To determine whether MSRB3 is also able to stereoselectively target oxidized methionine in actin, the repolymerization of MICAL-treated, pyrene-labeled actin was tested in the presence of full-length wild-type human MSRB3 (MSRB3WT) or a variant containing the p.Cys89Gly substitution (MSRB3Mut) that underlies human deafness DNFB74 (Ahmed et al., 2011). The gene discussed is MSRB3; the disease is deafness.