TABLE 3

Random spore analysis of two-point crosses

Type III cross (low)cType IV cross (high)c
MutationsaDistanceb (bp)ppmdDensityeppmdDensityeQuotientf
13 × 1 72 620 8.6  88012.30.70
13 × 5147 960 6.5 2,20014.80.44
13 × 142612100 7.9 4,60017.50.45
13 × 9371690018.5 7,90021.20.87
13 × 2481680014.1 9,50019.80.71
13 × 10605860014.212,00020.20.71
1 × 5 75 540 7.1  670 9.00.80
1 × 141891700 8.9 2,30012.00.74
1 × 9299550018.3 5,10017.11.07
1 × 2409500012.2 5,80014.30.86
1 × 10533570010.8 9,40017.70.61
5 × 14114 950 8.3 1,10010.10.83
5 × 9224370016.6 3,50015.81.05
5 × 2334480014.3 4,10012.41.16
5 × 10458600013.2 5,90012.81.03
14 × 91101100 9.9 1,40012.80.78
14 × 22201600 7.3 2,000 9.30.79
14 × 103442400 6.9 4,00011.60.59
9 × 2110 930 8.4 1,10010.20.83
9 × 102341900 8.2 2,40010.30.80
2 × 10124 480 3.9  750 6.00.64
  • a The mutation stated first is the one closer to the 5′ end of the gene.

  • b The distance between the mutation sites in base pairs.

  • c In type III crosses, the mutation closer to the 5′ end is in the h strain; in type IV crosses, it is in the h+ strain.

  • d Prototrophic recombinants per million spores (one experiment per cross).

  • e Prototrophs per million divided by base pairs (distance between mutations).

  • f Prototrophs per million of the type III cross divided by ppm of the type IV cross.