TABLE 3

Mutation rates per genome per replication in retroelements

ElementTarget (b)μgReferences
Retroviruses
Spleen necrosis viruslacZα (288)0.04aDrake (1993a)
Murine leukemia virusMLV (1380)≥0.06Drake (1993a)
tk (≥1128)0.26bParthasarathi et al. (1995)
Rous sarcoma virusRSV (1125)0.43Drake (1993a)
Bovine leukemia viruslacZα (288)0.027cMansky and Temin (1994)
Human immunodeficiency virus type 1lacZα (288)0.16dMansky and Temin (1995)
HIV-1 (9181)0.22e
Retrotransposon
S. cerevisiae Ty1Ty1 (173,043)0.11fGabriel et al. (1996)
  • a The data underlying this value are in Table 1 of Pathak and Temin (1990). That table described six mutations in the VP212-9 clone and added them to eight; in reality, there were seven mutations, which include F92 (described in their Table 2) (H. M. Temin, personal communication). The total of 37 mutations is correct.

  • b Of 244 tk mutants arising at f = 0.0882, 114 were of large extent and arose in a target of 2620 b and 130 were small and arose in a target of 1128 b. Among 49 sequenced small mutants, 28 contained non-BPS mutations and three contained nonsense mutations (B. D. Preston, personal communication). Following Drake (1993a), μg(large) = (0.0882/3)(114/244)/2620 = 0.524277 × 10−5 and μg(small) = (0.0882/3)(130/244)[28 + 3 × 64/3)/49]/1128 = 2.607 × 10−5 and μb(total) = 3.13 × 10−5. G = 8372.5 (Drake 1993a), so that μb = 0.262.

  • c Of 11 mutations in 18,009 288-b lacZα targets, eight were other than base pair substitutions and two were chain-terminating base pair substitutions. Thus, following Drake (1993a), f = 6.1 × 10−4, C = [8 + (2 × 64)/3]/11 = 4.6, and μb = Cf = 3.3 × 10−6. G = 8500 (Sagata et al. 1985).

  • d Of 69 mutations in 15,424 288-b lacZα targets, 24 were non-PBS and 10 were nonsense mutations. Thus, following Drake (1993a), f = 4.5 × 10−3, C = [24 + (10 × 64)/3]/69 = 3.4, and μb = Cf = 1.8 × 10−5. G = 9181 (Ratner et al. 1985).

  • e Using a combination of direct sequencing and single-strand conformational polymorphism analysis, and assuming an overall efficiency of mutation detection of 0.8, a total of 12 mutants were detected among 630,000 base replications (B. D. Preston, personal communication). Thus, μb = 12/(630,000 × 0.8) = 2.38 × 10−5 and μg = 0.219.

  • f The 13 base pair substitutions appear to have comprised only 10 mutational events; f = μ = 10/173043 per b and G = 5918.