Rare ER protein misfolding-mistrafficking disorders: Therapeutic developments

•Proteins in order to function need successful processes of transcription, translation, proper folding and trafficking.•We list and discuss a set of diseases where proteins lose function as they are misfolded due to mutations and as a consequence they are removed by cellular quality control machinery even though they can function if they reach correct destination.•We highlight the strategies being developed to correct the folding and trafficking defect to restore the protein function.