Do not the ends of the paired alleles have to coincide? Or can one
complete strand of DNA within a chromosome be longer than the other?

P van Rijckevorsel wrote:
Stewart Robert Hinsley wrote:
Different alleles are often, but not universally, of the same length. In
some cases they are distinguished by one or more base pair
substitutions. In others they are distinguished by the insertion or
deletion of lengths of DNA.

"Raphanus" schreef
OK. Now in a heterozygous gene the two alleles would have to be of
the same length - right?

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Why?
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Otherwise there would be a "kink" in one strand of the DNA spiral (?).

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Why?
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