There is some uncertainity around this gene. It for sure express itself with Schimmelpfennig Platinum. Called usually a dalmatian gene. It creates network of irregular black pattern. Usually on fins and forebody. It also affects other colors. Name galaxy is also often used to describe a phenotype build from Schimmelpfennig Platinum and Snakeskin. Goog example of this phenotype is popular tiger endler hybrid. I will use on this site a W. Storozhev approach – galaxy is an autosomal gene. It also shortens dorsal fin.
Bolesław Gaweł examples (not sure if all of below fish actually carry a galaxy gene)