Chapter 21.4, Problem 31AQP

(1)

Summary Introduction

To determine:

The locations of methylated and unmethylated cytosine in a DNA fragment $\text{(-ATCGC*GTTAC*GTTGC*GTCA-)}$ when researchers sequenced this fragment with or without treatment sodium bisulfite.

Introduction:

The addition of a methyl group to a deoxyribonucleic acid (DNA) molecule in order to change the chromatin structure that leads to cause a heritable change in the gene function or activity, is called DNA methylation. An example of DNA methylation is the cytosine methylation in which a methyl group is added to a cytosine nucleotide to produce 5-methylcytosine.

(2)

Summary Introduction

To give:

The sequences of bases that will be read with and without bisulfite treatment.

Introduction:

Sodium bisulfite treatment is used to determine the pattern of cytosine methylation in the DNA molecule. bisulfite treatment deaminate the unmethylated cytosine to form uracil by an the enzyme called deaminase.