Heterogeneity of the Silent Gene for Plasma Cholinesterase: Immunological Studies

Rocket immuno-electrophoresis and enzyme-linked immunosorbent assays were used to estimate the amount of cholinesterase present in 29 apparent silent homozygotes. 26 of these samples were segregated into four groups representing zero, very low, low and high levels of immunoreactive protein. These groups may represent the genotypes ${\text{E}}_1^s\,{\text{E}}_1^s$ ${\text{E}}_1^s\,{\text{E}}_1^t$, ${\text{E}}_1^t\,{\text{E}}_1^t$ and a new genotype ${\text{E}}_1^x\,{\text{E}}_1^x$, respectively. The possible genotypes of the remaining 3 individuals are discussed.