Class

Susceptible homozygotes

Heterozygote of susceptible alleles

Heterozygote with one R and one S allele

Heterozygote of resistant alleles

Resistant homozygotes


Genotype

S
_{
i
}
S
_{
i
}

S
_{
i
}
S
_{
i
}, i ≠ j

R
_{
i
}
S
_{
j
}

R
_{
i
}
R
_{
j
}, i ≠ j

R
_{
i
}
R
_{
i
}

Frequency

Θ

q
^{2}  Θ

2 pq

p
^{2}  Π

Π

Probability of Favorable Outcome

x

ax

bx

cx

dx

 Notation: Frequency of allele S
_{
i
}is q
_{
i
}; frequency of allele R
_{
i
}is p
_{
i
}. p =
p
_{
i
}; q =
q
_{
i
}= 1  p; ; . The subscripts of R alleles and the subscripts of the S alleles are unrelated.