Table 1.

Genotype Outcomes, Scores, and Probabilities for Affected–Unaffected Sib Pair

Affected sib Unaffected sib Sample
frequency score ( S) probability
AA AA n 22 0 m 22+ m (21) f 2 / 2(f 2 + f 1) +m 11 f 2 / 4(f 2 + 2f 1 + 1)
AA Aa n 21 1/4 m (21) f 2/ 2(f 2 + f 1) +m 11 f 2 / 2(f 2 + 2f 1 + 1)
AA aa n 20 1/2 m 11 f 2/ 4(f 2 + 2f 1 + 1)
Aa AA n 12 −1/4 m (21) f 1/ 2(f 2 + f 1) +m 11 f 1 / 2(f 2 + 2f 1 + 1)
Aa Aa n 11 0 m (21) f 1/ 2(f 2 + f 1) +m (20) + m 11 f 1/ 2(f 2 + 2f 1 + 1) +m (10) f 1 / 2(f 1 + 1)
Aa aa n 10 1/4 m (10) f 1/ 2(f 1 + 1) +m 11 f 1 / (f 2 + 2f 1 + 1)
aa AA n 02 −1/2 m 11/ 4(f 2 + 2f 1 + 1)
aa Aa n 01 −1/4 m (10)/ 2(f 1 + 1) + m 11 / 2(f 2 + 2f 1 + 1)
aa aa n 00 0 m (10)/ 2(f 1 + 1) + m 11 / 4(f 2 + 2f 1 + 1) +m 00