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. 2011 Jan;35(1):19–45. doi: 10.1002/gepi.20547

Table II.

Multinomial probabilities for genotype combinations in case/parent trios

Column index

1 2 3 4 5 6 7 8 9 10

Cell (row) index Genotypesagmgfgc Index of parental mating type P(dis|gm, gf, gc)bc P(gc|gm, gf)c P(gm, gf)cd assuming random mating and HWE P(gm, gf)c assuming only exchangeable parental mating types P(gm, gf, gc|dis)bce assuming only exchangeable parental mating types P(gm, gf, gc|dis)bce with reparameterization Σ = K/α µ1 = Inline graphic/Σ µ2 = 0.5Inline graphic/Σ µ3 = Inline graphic/Σ µ4 = 0.25Inline graphic/Σ µ5 = 0.5Inline graphic/Σ µ6 = Inline graphic P(gm, gf, gc|dis)bc with reparameterization Inline graphicIpInline graphicInline graphicInline graphicInline graphicInline graphicInline graphic
1 22 22 22 1 αR2S2ImIpγ22 1 Inline graphic Inline graphic Inline graphic R2S2ImIpγ22µ1 Inline graphic
2 22 12 22 2 αR2S2ImIpγ22 0.5 2Inline graphicA1 Inline graphic Inline graphic R2S2ImIpγ22µ2 Inline graphic
3 22 12 21 2 αR1S2Imγ21 0.5 2Inline graphicA1 Inline graphic Inline graphic R1S2Imγ21µ2 Inline graphic
4 12 22 22 2 αR2S1ImIpγ12 0.5 2Inline graphicA1 Inline graphic Inline graphic R2S1ImIpγ12µ2 Inline graphic
5 12 22 12 2 αR1S1Ipγ11 0.5 2Inline graphicA1 Inline graphic Inline graphic R1S1Ipγ11µ2 Inline graphic
6 22 11 21 3 αR1S2Imγ21 1 Inline graphic Inline graphic Inline graphic R1S2Imγ21µ3 Inline graphic
7 11 22 12 3 αR1Ip 1 Inline graphic Inline graphic Inline graphic R1Ipµ3 Inline graphic
8 12 12 22 4 αR2S1ImIpγ12 0.25 Inline graphic Inline graphic Inline graphic R2S1ImIpγ12µ4 Inline graphic
9a 12 12 12 4 αR1S1Ipγ11 0.25 Inline graphic Inline graphic Inline graphic R1S1Ipγ11µ4 Inline graphic
9b 12 12 21 4 αR1S1Imγ11 0.25 Inline graphic Inline graphic Inline graphic R1S1Imγ11µ4 Inline graphic
10 12 12 11 4 αS1 0.25 Inline graphic Inline graphic Inline graphic S1µ4 Inline graphic
11 12 11 21 5 αR1S1Imγ11 0.5 Inline graphic Inline graphic Inline graphic R1S1Imγ11µ5 Inline graphic
12 12 11 11 5 αS1 0.5 Inline graphic Inline graphic Inline graphic S1µ5 Inline graphic
13 11 12 12 5 αR1Ip 0.5 Inline graphic Inline graphic Inline graphic R1Ipµ5 Inline graphic
14 11 12 11 5 α 0.5 Inline graphic Inline graphic Inline graphic µ5 µ5
15 11 11 11 6 α 1 Inline graphic Inline graphic Inline graphic µ6 µ6
a

gm and gf refer to the unordered alleles in the mother and father respectively. gc refers to the ordered alleles (maternal/paternal) in the child.

b

dis indicates the event that the child is affected with disease.

c

(gm, gf) refer to the ordered parental genotypes (maternal, paternal).

d

A1 and A2 are the allele frequencies of allele 1 and 2, respectively.

e

Formulae for K and Σ are given in the Appendix.