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Mutation
Mutation – changes in the genetic materials.
Point Mutation – gene mutation involves changes in one
or a few nucleotides.
Frame shift mutations – the change of the nucleotide
shift the reading frame of the genetic message which
change the amino acid formation.
Types of Mutation
Deletion - Deletion is the loss of genetic
material. Any number of nucleotides can
be deleted, from a single base to an entire
piece of chromosome.1 Deletions can be
caused by errors in chromosomal
crossover during meiosis. This causes
several serious genetic diseases. Deletion
also causes frameshift.
Deletion
Before and after a deletion:
Addition (Insertion)
• In genetics, an insertion (also called an
insertion mutation) is the addition of one
or more nucleotide base pairs into a DNA
sequence.
• Insertions can be anywhere in size from
one base pair incorrectly inserted into a
DNA sequence to a section of one
chromosome inserted into another.
Addition (Insertion)
Before and after insertion
Duplication
• Gene duplication (or chromosomal
duplication or gene amplification) is any
duplication of a region of DNA that contains a
gene
• A duplication is the opposite of a deletion.
Duplications arise from an event termed unequal
crossing-over that occurs during meiosis
between misaligned homologous chromosomes
Duplication
Before and after duplication
Inversion
An Inversion mutation is a mutation that
causes a reversal in the order of a segment
of a chromosome within the chromosome, or
a gene.
Inversion
What happen during an inversion:
Translocation
• a chromosome translocation is a chromosome
abnormality caused by rearrangement of parts
between non homologous chromosomes.
• Translocations can be balanced (in an even
exchange of material with no genetic information
extra or missing, and ideally full functionality) or
unbalanced (where the exchange of
chromosome material is unequal resulting in
extra or missing genes).
Translocation
What happen during translocation:
Acknowledgement
• http://en.wikipedia.org/wiki
• Prentice Hall Biology Text by Miller Levine