Esterase D (ESD)

ESD encodes a serine hydrolase that belongs to the esterase D family. The encoded enzyme is active toward numerous substrates including O-acetylated sialic acids, and it may be involved in the recycling of sialic acids. This gene is used as a genetic marker for retinoblastoma and Wilson's disease.

Cowell et al. (1986) showed that there is a consistently lower level of esterase D enzyme activity in persons with the 2-2 phenotype when activity is measured in certain ways. They emphasized the importance of checking the electrophoretic phenotype before concluding that chromosome 13 deletion is present in a family being studied in connection with retinoblastoma (see later).