Abstract
A new esterase variant has been isolated by electrophoresis of homogenized testis, heart, and lung tissues. This esterase variant is genetically determined. The carrier strain was crossed with another in which the enzyme was not originally present; the presence of the enzyme was investigated in successive generations and in backcrosses to the carrier strain. Linkage was found with other esterases in linkage group V, while there was independent segregation from the immunogenetic markers Ly-1, Ly-2, LH-1, and R1-1a.