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How to distinguish linkage and crossover?

  1. Mar 28, 2005 #1
    I really dunno how to distinguish beween 2 things, it's based on the ratio right?
  2. jcsd
  3. Mar 29, 2005 #2


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    A cross-over is the exchange of segments between two homologous chromosomes of linked genes/genetic loci.

    Linkage is the association of gene or genetic loci and that will likely be transmitted together during recombination/cross over.

    for example you have following genetic loci:

    Code (Text):

    A B C D E F G H I
    a b c d e f  g h i
    gene C D E and F are linked

    so during recombination gene/repeats are exchange as follow

    Code (Text):

    a B  c d e f G h I
    [B]A[/B] b [B]C D E F[/B] g [B]H[/B] i
    So when you look at the phenotype/genotype you will always see that C D E and F are always together and have the same frequency, and that the frequency of A, B, G, H, and I is indepent of each other
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