Sampling

VARIANCE OF GENE FREQUENCY

  • The change of gene frequency Δq resulting from sampling in one generation can be stated in terms of its variance
    • This variance of Δq expresses the magnitude of the change of gene frequency resulting from dispersive process.
    • In the next generation, the sampling process is repeated starting from the gene frequency in the previous generation.
    • The effect of continued sampling through successive generations is that each line fluctuates irregularly in gene frequency and the lines spread apart progressively, thus becoming differentiated.
    • Sooner or later each line must reach the limits of 0 or 1.
    • When a particular allele frequency has reached 1 it is said to be fixed in that line and if it reaches 0 it is lost.
    • When a particular allele is fixed in all individuals in a line; all are identical for that genotype and become genetically identical.
    • This is the basis of the genetic uniformity of highly inbred strains.

Variance of gene frequency change

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Last modified: Saturday, 23 July 2011, 7:32 AM