The Cholinesterase Variants and Multiple Forms

Other genes controlling the synthesis of plasma cholinesterase are suspected to exist, as evidenced by anomalous results obtained in studies of some individuals and families. Because all the cholinesterase genotypes have not yet been discovered, some of the genotypes assigned to certain individuals may eventually be found to be in error. The limited sen- 

It is unfortunate that a standardized system of nomenclature has not been adopted by workers in this field. Systems of nomenclature have been proposed by Motulsky (M18), by Lehmann and Liddell (L22), and by Goedde and Baitsch (G19, G20). All three systems continue in use to varying degrees. However that proposed by Motulsky (M18) appears to be the most widely accepted and applied, and it is therefore us in this review. 

The genes at the Eg locus, which affect the isozyme pattern of the enzyme, are called Eg for the more common variant, and Ej for the less common variant. Various means of designating the multiple forms of cholinesterase, which can be characterized from their electrophoretic properties, are considered in Section 2.6. 

The different systems of nomenclature of the variants, and some of the properties of the cholinesterases present in the plasmas of individuals of the reported genotypes, are summarized in Table 1. 

A major advance in understanding the cause of hypersensitivity to suc-cinylcholine came in 1957 when Kalow et al. (Kll, K12) reported an in vitro method for detecting the presence of atypical serum cholinesterase in human plasma. Kalow and Staron (K15) reported that the inheritance of the atypical enzyme variant is caused by an autosomal gene without 

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