A V1865L amino acid replacement (coordinates of the cher-PA isoform), along with a PBac{ScarlessHD-DsRed} marker element have been introduced into the endogenous cher locus. The V1865L change is equivalent to a V2375L change in the orthologous human FLNC gene, a variant identified in patients with hypertrophic cardiomyopathy. The presence of the PBac{ScarlessHD-DsRed} marker element introduces a premature stop codon, resulting in a truncated protein deleted from cher residue 1876 (coordinates relative to the cher-PA isoform).