Biochemistry - The Chemical Reactions of Living Cells Volume 3 - D. Metzler 1980

Biochemical Genetics and the Synthesis of Nucleic Acids and Proteins
Recombination, Integration, and Excision
Unequal Crossing Over

For recombination to occur, homologous regions of two DNA molecules (or, in the case of Meiosis, two chromatids) must come into close proximity. Because repetitive sequences occur in DNA (either by chance or for some other reason), Crossing-over can occasionally take place between two regions of double-stranded molecules that are not strictly identical. During such unequal crossing-over, one of the resulting molecules becomes elongated, while the other is shortened. This phenomenon may well be a crucial factor in evolution [232a].



Last update: 06/08/2026

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