COMP and psychosocial stress measurement: PSACH is another classic ER stress–related disease10; however, numerous previous studies using bothin vitro22,23 andin vivo24,25 models have unequivocally demonstrated that ER retention of mutant COMP induces ER overload response (EROL)26 that comprises oxidative stress and inflammation potentially mediated by nuclear factor kappa B (NF-κB) as opposed to a ‘classic’ UPR10.