Page 201 - Linear Models for the Prediction of Animal Breeding Values 3rd Edition
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Table 11.1. Solutions for mean and SNP effects from various models.
                                         Unweighted                Weighted
               Mean effect
                                            9.944                   11.876
               SNP effects solutions
                  1                         0.087                   –0.633
                  2                        −0.311                   −3.041
                  3                         0.262                    3.069
                  4                        −0.080                   −1.267
                  5                         0.110                    2.600
                  6                         0.139                    4.447
                  7                         0.000                    0.000
                  8                         0.000                    0.000
                  9                        −0.061                   –3.240
                  10                       −0.016                    1.883

               Table 11.2. Direct genomic breeding (DGV) values from various models.

                                                       Selection  SNP-BLUP
                                   SNP-BLUP   GBLUP      index    (weighted)
               Reference animals
                  13                 0.070      0.069    0.070     –2.651
                  14                 0.111      0.116    0.111      1.307
                  15                 0.045      0.049    0.045      0.611
                  16                 0.253      0.260    0.253      1.007
                  17                 0.495     –0.500   –0.495     –5.693
                  18                –0.357     –0.359   –0.357     –4.358
                  19                 0.145      0.146    0.146      0.502
                  20                –0.224     –0.231   –0.225     –5.718
               Selection candidates
                  21                 0.027      0.028    0.028     –0.006
                  22                 0.114      0.115    0.115      6.513
                  23                –0.240     –0.240   –0.240     –3.835
                  24                 0.143      0.143    0.143      2.701
                  25                 0.054      0.054    0.054      3.273
                  26                 0.354      0.353    0.353      6.350

        Noting that:
                     2
            s =    s g
             2
             a
                2Σp(
                   j 1 p )−  j
        then the matrix ZZ′ can be scaled such that:
            G=    ZZ ′
               2 ∑ p ( 1 −p)
                       j
                   j
                     2
        and var(a)=Gs . The above division scales G to be analogous to the numerator rela-
                     a
        tionship matrix (A). The genomic inbreeding coefficient for individual i is G  – 1, and
                                                                         ii
        the genomic relationship between individuals i and k, which are analogous to the
        relationship coefficients (Wright, 1922), can be obtained by dividing the elements G
                                                                                 ij
        by the square roots of the diagonals of G  and G . The matrix G is generally positive
                                            ii     jj
        Computation of Genomic Breeding Values and Genomic Selection         185
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