A cross is made between an Hfr strain that is Str^Sa⁺b⁺d⁺ in genotype and an F^- strain that is Str^Ra^-b^-d^- in genotype.Interrupted-mating studies show that b⁺ enters the recipient strain last,and that the Str locus is very far away from b⁺,so it never enters the recipient strain.The b⁺ recombinants are then tested for the presence of the a⁺ and d⁺ alleles.The following data were obtained: $\begin{array} { l l l l } a ^ { + } & b ^ { + } & d ^ { + } & 326 \\a^ { -} & b ^ { + } & d ^ { + } & 2 \\a ^ { + } & b ^ { + } & d^ { -} & 14 \\a ^ { -}& b ^ { + } & d ^ { -}& \underline { 58 } \\& && 400\end{array}$
a) What is the gene order?

Question

A cross is made between an Hfr strain that is Str^Sa⁺b⁺d⁺ in genotype and an F^- strain that is Str^Ra^-b^-d^- in genotype.Interrupted-mating studies show that b⁺ enters the recipient strain last,and that the Str locus is very far away from b⁺,so it never enters the recipient strain.The b⁺ recombinants are then tested for the presence of the a⁺ and d⁺ alleles.The following data were obtained:

\begin{array} { l l l l } a ^ { + } & b ^ { + } & d ^ { + } & 326 \\a^ { -} & b ^ { + } & d ^ { + } & 2 \\a ^ { + } & b ^ { + } & d^ { -} & 14 \\a ^ { -}& b ^ { + } & d ^ { -}& \underline { 58 } \\& && 400\end{array}

a) What is the gene order?

Quizplus · Accepted Answer

The Answer is D

A Cross Is Made Between an Hfr Strain That Is