From Alberts, B. et al. 1994. Molecular Biology of the Cell.  Garland Publishing, New York, NY.

Diagram of Drosophila polytene chromosomes showing chromosome banding.
 

From Alberts, B. et al. 1994. Molecular Biology of the Cell.  Garland Publishing, New York, NY.

Effect of inversion on recombination.  In (B), the location of the inversion is evident from the positions of genes A, B, C, etc. on the two chromosomes.  Pairing during meiosis creates an inversion loop, and crossing over produces four types of gametes, only two of which are functional.  Recombination is effectively suppressed because viable gametes contain only non-recombinant chromosomes.  The genes within the inversion are thus inherited as a block or "supergene".
 
 
 
 
 
 
 

From D. J. Futuyma.  1998.  Evolutionary Biology.  Sinauer, Sunderland, MA.
 
 
 
 
 
 
 
 
 
 

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