I would like to find out how to use the Lander MAPMAKER program to
analyze F2 intercross data for mapping when the homozygous recessive
for one marker is partially lethal. For example, when that marker gives a
distorted Mendelian ratio of (say) 7:1 in F2, instead of 3:1, due to partial
embryo lethality. I would appreciate if someone comments on this.