Biochemical genetics of Es-14 (formerly Es-Si) and a new esterase variation, Es-15, of the laboratory rat (Rattus norvegicus): biochemistry, tissue expression, and linkage to Es-1 in linkage group V.

The segregation of rat esterases controlled by loci residing in linkage group V (LGV) has been studied in two backcross series, (LEW/Han X BN/Han)F1 X LEW/Han and (LEW/Han X LE/Han)F1 X LEW/Han. Es-14 (formerly Es-Si) was shown to be closely linked to Es-1. A new esterase locus, Es-15, was described which codes for a liver isozyme. The distribution pattern of three alleles at the Es-15 locus is presented for 52 independent inbred strains. Close linkage of Es-15 to Es-14 and to Es-1 was established, proposing the following gene order: [Es-2, Es-10]-[ES-1, ES-14, ES-15]. The esterase loci on LGV are thus separated into two gene clusters, cluster 1 and cluster 2. These conclusions are supported by the strain distribution patterns of the two RI strain series, LXB and DXE.