Chapter 5, Problem 26P

Summary Introduction

To analyze:

Considering cross between a trihybrid wild type plant to a plant with the recessive phenotypes answer the following using data in the given table.

Phenotype	Number
Compound leaves	$\text{324}$
Compound leaves, intercalary leaflets	$\text{32}$
Compound leaves, green fruits	$\text{5}$
Compound leaves, intercalary leaflets, green fruits	$\text{51}$
Intercalary leaflets	$\text{3}$
Intercalary leaflets, green fruits	$\text{3}0\text{9}$
Green fruits	$\text{42}$
Wild type	$\text{49}$
	$\text{815}$

1. The order of genes on the chromosome, alleles that are present on each of the homologous chromosomes.

2. The recombination frequencies between each of the adjacent pairs of genes.

3. The interference value for the given cross.

Introduction:

To determine the order of genes on the chromosome and alleles present on each of the homologous chromosomes, phenotype information about pure-breeding parental plants is used. According to the given information, the parent plants are pure-breeding dominant and pure-breeding recessive. Recombination frequency for a pair of linked genes is calculated by counting the total number of crossovers occurring between them. Interference is used to identify the proportion of double recombinants that are expected but are not produced in the experiment.