bsc biotechnology

1. MUTATION
BY
>>AZIMA FATIMA

2. what is mutation?
>>Such sudden heritable
change in genetic material is called
mutation.
>>The process is called mutagenesis
and the affected organism is called
mutant.

3. Types of mutation
• chromosomal mutation :- structural change in
chromosome
• Gene mutation :- change in gene
• On the basis of occurrence they are of two
type:-
• Somatic mutation
• Germinal mutation

4. How does mutation
occur?
• According to origin mutation proceed by 2-way~
• Spontaneous mutation - they are the mutation
which develop due to internal cause without any
relation to the external factor of the environment.
• How it occurs
• During replication wrong nucleotide enter in the
chain
• Toumers
• these are mutation which develop in response

5. Induced mutation
• to external environmental factors.
• Eg-biological mutagen
Viruses
*physical mutagen - "uv - rays, ionising radiation,
temperature
*chemical mutagen-" nitrous acid, hydroxylamine etc.

6. Method of gene mutation
• 1.substitution - (replacement) -it involves
one or more nitrogen bases with other.
it is of two types :-
*transition :- A purine is replaced to the
another purine (A and G) while pyrimidine with
pyrimidine (C, T)
* transversion :-there is a replacement of
purine (A, G) with pyrimidine (C, T).

7. Frame - shift mutation
>> it is a gene mutation where the reading
codon is changed due to detection or insertion
of nucleotide.
They are of two types :-
*"insertion :- there is a insertion of one or
more nucleotide inside the gene.
ATT CGC TGA = AGT TCG CTG A
ATT CGC TGA = ACG TTC GCT GA

8. DELETION
>>one or more nucleotide slip out of gene changing the
reading of the frame in backward direction.
ATT CGC TGA = ATC GCT GA
deletion of T.
ATT CGC TGA = AGT TCG CGA
deletion of TT
both insertion ND deletion occur :-
Insertion of G
ATT CGC TGA = AGT TCG CGA
Deletion of T.

9. Importance of Mutation
• Beneficial importance :-
• Without mutation the gene exist in one form
No alles found
* it is ultimate source of all variations.
*Raw material for evolution.
*it is able to evolve ND adapt to environmental
change
Ex:- protection against HIV.

10. HARMUFUL effects
• Mutation can cause error in protein sequence
creating non functional protein. It can cause genetic
disorders
• Ex:- A drosophilla with leg grown over the head
• Six finger develops in a palm