J. M. PATEL ART COMMERCE AND

SCIENCE COLLEGE

SEMESTER -2nd sem.

PRESENTED BY

DR.VEENA M. MAHAJAN

DNA DAMAGE AND

REPAIRE

CONTENT

Introduction

Types of DNA Damage

Types of mutation

DNA repair mechanism

Excision Repair

Mismatch Repair

Recombination repair

Double strand DNA break repair

WHAT IS DNA

A nucleic acid that carries the

genetic in formation in cell &some

viruses consisting a two long chain of

nucleotide twisted in double helix

DNA DAMAGES

Types of damages

Mutation

Types of mutation

1. point mutation

transition and transversion

2. frameshift mutation

addition and deletion

1. POINT MUTATION

TRANSVERSION AND TRANSITION

2.FREAMSHIFT MUTATION

Addition and deletion causing shift

1.mutation in single stranded break :-ex. peroxide

2.DOUBLE STRAND BREAK (DS BREAK)

T-T dimmer mutation :-

Repair enzyme

photolygase in this dimmer.

•INTERCALATION

AFFECT OF DYES IN MUTATION

Acridine dyes : yellow, orange , red

Ethidium bromide :it’s a aromatic &

flourscent compound

Acriflovin :It is antiseptic & orange,

brown in colour

Proflavin : used urinary antiseptic

•CROSSLINKING MUTATION

like mitomycin C

•APURINATION & APYRIMIDINATION

BREAKAGE OF N-GLYCOSYLIC BOND IN BASE

DNA REPAIR MECHANISM

1.Excision repair

it consist of a two repair process

DNA glycosylase

NUCLEOTIDE EXCISION REPAIR

2.MISMATCH REPAIR

It consist two types of repair

mechanism

Recombination repair

Double strand DNA break

mechanism

1. RECOMBINATION REPAIR

BREAK DNA DOUBLE STRAND

REPAIR

THANK YOU