Chapter 12.5, Problem 17COQ

Summary Introduction

To explain:

The way through which the type of cleavage of the Holiday intermediate leads to noncrossover recombinants and crossover recombinants.

Introduction:

Exchange of genetic information among DNA homologous molecules is termed as “homologous recombination”. Recombination is an essential genetic process and important for crossing over and DNA repair mechanisms.

Homologous chromosomes align and their single nucleotide strand pairs with its complementary strand by creating a nick leads to form a “heteroduplex DNA molecule”.

A single-stranded nick in each two DNA strand can lead to form a “Holiday junction”. In holiday junction, recombination occurs through single-strand nicking, displacement of the strand, branch migration and resolution of a single Holiday junction.