Crossover Frequency Between Lz and Su

Crossover between any two loci must include the double-crossover events. For example, the crossover frequency between Lz and Su:

Lz su gl 40
lz Su Gl 33
Lz su Gl 4
lz Su gl  2

= 79

79/740 = 10.7% crossover between Lz and Su. The map distance between these loci is 10.7 m.u.

Lz Su gl 59
lz  su Gl 44
Lz su Gl 4
lz Su gl  2

= 109

109/740 = 14.8% or 14.8 units between Su and Gl. It makes sense to include double-crossovers twice, since two crossover events occurred. Double-crossovers were included once in calculating Lz to Su distance and once again when calculating Su to Gl distance.

The resulting map is: