To determine the middle locus in a three-point cross, compare the double-crossover progeny with the nonrecombinant progeny. The double crossovers will be the two least-common classes of phenotypes; the nonrecombinants will be the two most-common classes of phenotypes. The double-crossover progeny should have the same alleles as the nonrecombinant types at two loci and different alleles at the locus in the middle.
-A three-point test cross is carried out between three linked genes.
The resulting nonrecombinant progeny are s⁺ r⁺ c⁺ and s r c and the double-crossover progeny are s r c⁺ and s⁺ r⁺ c. Which is the middle locus?

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The Answer of To determine the middle locus in a three-point cross, compare the double-crossover progeny with the nonrecombinant progeny. The double crossovers will be the two least-common classes of phenotypes; the nonrecombinants will be the two most-common classes of phenotypes. The double-crossover progeny should have the same alleles as the nonrecombinant types at two loci and different alleles at the locus in the middle. -A three-point test cross is carried out between three linked genes. The resulting nonrecombinant progeny are s⁺ r⁺ c⁺ and s r c and the double-crossover progeny are s r c⁺ and s⁺ r⁺ c. Which is the middle locus?

To Determine the Middle Locus in a Three-Point Cross, Compare