CLRN1 and Usher syndrome: An additional small molecule that has been of interest for Usher syndrome treatment, known as BioFocus 844 (BF844), was identified through cell-based high throughput screening as capable for stabilising the defective Clarin-1 protein produced by the common CLRN1 missense variant p.(Asn48Lys).138 BF844 was shown to protect against progressive hearing loss when administered intraperitoneally to an Usher 3 knock-in mouse model.