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Contribution of T.H. Morgan in genetics.

  1. T. H. Morgan had discovered the phenomenon of linkage.
  2. He was the first who crossed mutant yellow bodies and white eyed females with wild types male (gray bodies, red eyed).
  3. The F1 females were wild type, whereas the F1 males expressed both mutant traits.
  4. In the F2 generation, 98.7% of the total offspring showed the parental phenotype (yellow bodied, white eyed flies) and wild type flies (gray bodied, red eyed).
  5. The remaining 1.3% of the off springs was there with recombinant feature develop as a result of separation of genes.
  6. Depending on this theory Morgan suggested that separation of linked genes occur due to formation of chiasmata which represent points of genetic exchange.
  7. He also introduced the term “crossing over” that describes the physical exchange leading to recombination.
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