Table 1.
Rate of Transmission of Variant Allele from Heterozygous Parents, as a Weighted Average of Mating-Type–Specific Transmission Rates across Informative Mating Types
| Informative ParentalMating Type | Proportion of Parents (of Cases) with Given Mating Typea | Proportion of Heterozygous Parents (of Cases) with Given Mating Type | Mating-Type–SpecificTransmission Rate |
| (1,2) | π12 | π12/π12+2π11+π01=w12 | R2/R1+R2 |
| (1,1) | π11 | 2π11/π12+2π11+π01=w11 | R2+R1/R2+2R1+1 |
| (0,1) | π01 | π01/π12+2π11+π01=w01 | R1/1+R1 |
| Weighted averageb | w12 R2/R1+R2+w11 R2+R1/R2+2R1+1+w01 R1/1+R1 |
a
Under the assumption of mating symmetry, the conditional probability that parents have the given mating type, given that their child is affected; that is πij=P[(M,P)=(i,j) or (j,i)∣D].
b
This weighted average equals the transmission rate.