TGFBI-related corneal dystrophies are disorders characterized by accumulation of the abnormal protein product of TGFBI gene in the nonamyloid or amyloid form due to missense gain of function mutations of this gene. TGFBI gene exists in the zebrafish genome without duplication and has 65% homology to its human ortholoque. Arginine residue on the 124th position of the protein product of this gene was conserved in zebrafish. According to these data; in this study we tried to knock-in one of the gains of function mutations in the region coding 124th aminoacid residue of TGFBI gene in the zebrafish genome by using CRISPR/Cas9- mediated homology dependent repair method that resulted in many challenges in zebrafish. Finally, we could not achieve knockin of the precise mutation in the target sequence despite using several possibilities regarding CRISPR/Ca9 technique, but we could achieve in/del variations at the target sequence that could mimick the pathogenesis if the variation results in inframe change affecting the target arginine residue.