TABLE 2

Number of substitutions in three lineages and dispersion index in eight genes from regions of normal recombination rates

SynonymousReplacement
Number of substitutionsDispersion indexNumber of substitutionsDispersion index
GeneLengthD. melanogasterD. simulansD. yakubaLengthD. melanogasterD. simulansD. yakuba
Adh199.47.9 (8.4)3.2 (4.7)23.5 (21.0)0.4565.61.5 (1.5)1.0 (1.0)5.0 (5.0)0.1
per410.834.4 (30.8)15.6 (21.8)93.4 (75.3)0.61268.21.3 (1.3)1.2 (1.6)29.4 (28.9)7.5
Amy-p356.623.0 (21.0)10.1 (10.0)20.6 (18.5)2.71122.510.1 (10.0)1.0 (1.0)10.1 (10.5)4.3
sry412.142.3 (35.3)8.4 (11.3)70.1 (57.3)4.71043.910.2 (10.0)1.9 (2.0)19.4 (19.0)2.3
nullo136.810.5 (8.3)2.4 (4.3)61.7 (42.8)8.4384.23.0 (3.0)5.1 (5.0)18.8 (18.5)1.1
G6pd377.720.1 (18.2)22.0 (20.2)36.0 (31.7)7.61177.35.0 (5.8)17.3 (17.8)14.2 (14.3)10.9
boss416.323.0 (22.2)14.5 (16.6)55.0 (47.4)0.41149.74.4 (4.4)0.4 (0.4)1.6 (2.0)2.8
Rh3307.014.6 (13.9)11.0 (14.3)35.9 (31.8)0.8839.03.0 (3.0)0.0 (0.0)0.0 (0.0)3.3
Total175.8 (158.2)87.1 (103.4)396.3 (325.9)38.4 (39.0)28.0 (28.8)98.7 (98.2)
  • The number of substitutions in the three lineages was calculated from the number of substitutions in the three species pairs, which was derived from the product of the number of synonymous or replacement sites and Kimura's (1980) estimate of the number of substitutions per site. Numbers in parentheses are the number of substitutions inferred on parsimony assumptions (see materials and methods). Following Gillespie's (1989) method, dispersion indices for synonymous and replacement substitutions were weighted by synonymous and replacement weight factors, respectively. These factors were calculated from the pooled number of substitutions in the three lineages: 0.800 for the D. melanogaster, 0.396 for the D. simulans and 1.804 for the D. yakuba lineage in synonymous substitution; and 0.698 for D. melanogaster, 0.509 for D. simulans and 1.794 for D. yakuba in replacement substitution. The totals do not, in many cases, match the sum in the columns due to the accumulation of rounding errors.