Mutation

1. MUTUATION
SUBMITTED TO: DR.FIRASAT HUSSAIN
SUBMITTED BY: MUHAMMAD HUSSAIN TAQI

2. MUTUATION
 What is mutation?
The changing of the structure of a gene, resulting in a variant form that may be transmitted to
subsequent generations, caused by the alteration of single base units in DNA, or the deletion, insertion,
or rearrangement of larger sections of genes or chromosomes.
 ."mutation is, ultimate way for new variation in the species"
• Types of mutation.
• Point mutation
• Frameshift mutation
• Chromosomal alterations

3. MUTUATION
 Point mutation.
change in a single nucleotide or single base in DNA.
Further have three kinds.
• Silent
• Missense
• Nonsense

4. MUTUATION
• Silent.
 Mutated codon codes for the same amino acid
 CAA (glutamine) → CAG (glutamine)
 Effect none
• Missense.
 Mutated codon codes for a different amino acid
 CAA (glutamine) → CCA (proline)
 Effect Variable
• Nonsense.
 mutated codon is a premature stop codon
 CAA (glutamine) → UAA (stop)
 Effect Usually serious

5. MUTUATION
Frameshift mutation.
Deletion or insertion of one or more nucleotides pairs.
AUG-AAU-GCU= Asparagine-threonine-alanine
AUG-AAA-UAC-GGC-U= lysine-tyrosine-glysine

6. MUTUATION
• Chromosomal alternation.
That chage chromosome structure,break off and rejions incorrectlyor does not rejion of section.

7. MUTUAGENIC AGENTS.
 Mutagen.
Mutagen is a chemical or physical agent capable of inducing changes in DNA.
 Chemicals
 Radioactive substance
X.rays
 UV radiation

8. MUTUAGENIC AGENTS.
CHEMICALS.
Chemical products that cause mutation are chemical mutagens.
Medicines(drugs)
Nitrius acid
Ethylmethane sulfonate

9. MUTUAGENIC AGENTS.
• Radiation as a Mutagen.
It is a enviormental mutagen that may cause direct changes in a cell’s DNA.
 Break DNA sequence leading to chromosome rearrangment.
 lower energy penetrate nuclear membrane.
• UV rays lead to thymine dimers by harmful covalent bonds between pyrimidines

10. MUTUAGENIC AGENTS.
Repair.
Photolyases light repair enzymes use energy from visible light to fix UV light damage,by seprate dimers
back to original two thymines.
• Some mistakes corrected immadietly proofreading process during replication.
• Some corrected after replication called mismatch repair.
• Supression of mutation in DNA.
By introducing a second mutation elsewhere in the mutated gene,results partial or
complete loss of function in its product.

12. THANK YOU