| Abstract: | ![]()
To date, mutations in mutants representing 19 of the 33 recognized HSV-1 complementation groups have been mapped. The physical map locations of mutations in 10 ts mutants of HSV-1 strain KOS representing 8 of the 19 complementation groups are reported herein. The mutations in three mutants were found to lie between coordinates 0.086 and 0.194—two of these were mapped finely to between coordinates 0.095 and 0.108—and in seven mutants, between 0.301 and 0.448. The mutation in 1 of the 10 mutants tsQ26, was mapped finely to a sequence between 500 and 1000 base pairs to the left of the 3′ end of the TK gene (0.301–0.304). The availability of physical mapping data has (1) confirmed the usefulness of the complementation test as a means of identifying viral gene functions, (2) facilitated the rapid assignment of mutants to new and recognized cistrons, and (3) prompted a reevaluation of previously ambiguous complementation for mutants in 2 complementation groups. Thus, the 10 mutants whose ts mutations were mapped in this study had been assigned previously to 8 complementation groups based on the assumption that complementation indices of 2 or greater signified that 2 mutants were in different genes. Combined with physical mapping data, however, the results of complementation tests now indicate that indices between 2 and 10 may reflect either inter- or intragenic complementation. Thus, the 10 mutants have now been assigned to 7 complementation groups. Although physical mapping data have confirmed the results of previous complementation tests for 6 of 8 groups analyzed, reevaluation of complementation data in the light of physical mapping data has resulted in a more precise genetic definition of the locus for viral DNA polymerase and of a locus (represented by mutants in complementation group 1–10) which maps in the left hand portion of UL. |
