Originally Posted by
RickF
Actually, I think you just proved that gin rin is dominate.
If gin rin was recessive and all of the possible parents were gin rin, then none of the parents could possibly carry the gene for normal scales, so 100% of the offspring would be gin rin. If gin rin is dominant, all of the parents could carry the normal scale gene. If it is a single gene and all of the parents are heterozygotic, then you should get 75% gin rin and 25% normal scales. If some of the parents are homozygotic and some are heterogotic, then you should get more than 75% gin rin. Assuming the presence of gin rin did not influence which fry survived, it looks as if more than one gene must be involved.