define paralog
Noun [edit]. paralogue (plural paralogues). ( 1 genetics) either of a pair of genes that derives from the same ancestral gene. ( 2 genomics) a pair of genes that derives from the same ancestral gene and now reside at different locations within the same genome.
They also found an important change in the type-2 deiodinase paralog in the gills. The gills are important for regulating the salt balance in the fish. In the study, they found that this deiodinase paralog that activates the thyroid hormone in the gills only increases when the fish reaches saltwater.