The document discusses different types of mutations including chromosomal mutations and genetic mutations. It defines gene mutations as mutations that change the function of a gene by altering its polynucleotide sequence. The types of gene mutations described include insertion, deletion, inversion, substitution, duplication, silent mutation, missense mutation, nonsense mutation, and frameshift mutation. Each mutation type results from a different change to the gene sequence, such as the addition, removal, inversion, or replacement of nucleotide bases.

1. GENETICS
PRESENTATION
SRISHTI
BSc. Hons. Biochemistry
Department Of Chemistry & Biochemistry
School Of Basic Sciences & Research
Sharda University

2. MUTATION
“Change in the nucleotide sequence of the DNA”
“Due to the replication errors, exposure to
mutagens and viral infections changes or
alterations occur in a DNA sequence which causes
genetic abnormalities, known as mutation.”
Types Of Mutations
1. Chromosomal Mutations
2. Genetic Mutations

3. GENE MUTATION
‘Mutation or series of mutations occur in the
polynucleotide sequence of a gene that
changes the function of it is referred to as
gene mutations’
Point Mutation– Change in the single base
of the DNA. It’s often known as single
nucleotide polymorphism.

4. Type Of Gene Mutations
• INSERTION
• DELETION
• INVERSION
• SUBSTITUTION
• DUPLICATION
• SILENCE MUTATION
• MISSENSE MUTATION
• NONSENSE MUTATION
• FRAMESHIFT MUTATION

5. 1. Insertion– insertion or addition of a
base into the gene sequence. Often known as
addition mutation.

6. 2. Deletion– When a base or some bases
deleted from the gene sequence.

7. 3. Inversion– When some gene
sequences inverted and inserted back into
the original sequence.

8. 4. Substitution– When some bases of a
gene sequence are replaced by other
bases.

9. 5. Duplication– when some bases or
a base duplicated in a gene
sequence.

10. 6. Silent Mutation:
• It is non-expressive. In silent mutation, a new codon
codes for the same amino acid as the wild-type one.
8. Missense Mutation:
• A codon originated from a nucleotide change that will
code for different amino acids. It can lead to alteration
or loss of function in protein.
7. Nonsense Mutation:
• A stop codon added to the DNA sequence that stops
protein translation. It stops protein synthesis because
a stop codon ends the protein synthesis results in a
premature protein or truncated protein.

12. 7. Frameshift Mutation:
• Base pair alteration causes abnormal reading frames
which ultimately results in an abnormal protein
formation. There can be insertional or deletion
frameshift mutation.