From out of old fields comes all this new corn:

1
1
Coefficient of Inbreeding

• Inbreeding is due to mating of individuals that
  are more closely related through common ancestry
  than are individuals taken at random from the
  population.

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2
3
3
F the coefficient of inbreeding

• Wright (1921, 1922)
• Is the probability that two alleles at a locus
  are identical by descent
  
• Computation requires tracing the pedigree back to
  common ancestors and computing the probabilities
  at each segregation
  

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4
(A a)
What is Fx ?
5
5
6
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7
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8
8
9
9
10
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11
11
12
11
13
12
14
13
15
15
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Proportion of homozygotes in any generation

• For a single locus
• homozygotes 1 - (1/2)m
• Where m number of generations of selfing
• m 1, then 0.5
• M 3, then 0.875

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17
Proportion of homozygotes in any generation

• For more than one locus, extend model
• homozygotes ((2m-1) / 2m )n
• where m number of generations of selfing
• n number of loci
• 3 generations, with 3 genes then 0.669
• 5 generations, with 5 genes then 0.853

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18
0
Number of Independently inherited loci
25
15
10
Percentage of homozygotes
5
50
1
75
100
Generation
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19