Define point mutations. Distinguish between base-pair substitutions and base-pair insertions. Give examples of each and note the significance of such changes.

Point mutation is a mutation affecting just a single gene,it involves the deletion or modification or insertion of a single Nucleotide base in a Genetic sequence of RNA OR DNA.

Base pair substitution is the replacement of a Nucleotide base pair by another.

Base pair insertion is the addition of a Nucleotide base to a DNA.

Examples of Base pair substitution CAN BE SEEN IN THE SICKLE CELL ANEMIA.

Example of Base pair insertion CAN BE SEEN IN HUNTINGTON'S DISEASE AND FRAGILE X SYNDROME.

SIGNIFICANCE:base pair substitution can cause a MISSENSE MUTATION.

Base pair insertion can cause the WRONG AMINO ACIDS TO BE ADDED or can cause EARLY TERMINATION of the amino acid chain.

Explanation: Mutation is an undesired change that take place in the Genetic make up of an organisation. This change can be beneficial and can also be adverse like in the case of SICKLE CELL ANEMIA.

This substitution can be by SUBSTITUTION OR BY INSERTION.

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