Analysis without  grandparents

In family 2, the father carries both A and B, but it is not known whether he inherited  them from the same parent or from different parents. Hence, if there is linkage, he may be of constitution AB/ab or Ab/aB. The mother is ab/ab. Of the five children, two are AB/ab, two ab/ab, and one aB/ab.

Case I - assume father is AB/ab

then four children would be non-recombinant each with a probability of (1-f) and one would be recombinant with a probability of f.

The combined probability would then be f (1-f)4

Case II - Assume that the father is Ab/aB

then four children are recombinant, each with frequency of f;
 one is non-recombinant = (1-f)

The probability of the observed sequence of 1 non-recombinant and 4 recombinants = (f4)(1-f).

P = [f(1-f)4 +(f4)(1-f)]/2

Combining both analyses


Text iGenetics by Peter J. Russell


This web site is provided for instruction in Botany and Zoology 342

by Kenneth G. Wilson,
Professor of Botany
Miami University
wilsonkg@muohio.edu