Transcript Mutations Table PowerPoint

Protein Synthesis
Types of Mutations Graphic Organizer
Point vs. Gene Mutations
Point Mutations only affect a SINGLE nitrogen
base.
May not cause any noticeable mutation if the amino acid is not
changed.
May also occur in the buffer or junk zones of DNA
Chromosomal Mutations affect entire or sections
of a chromosome
Multiple Genes are affected
Always causes some type of change.
Substitution
One Nitrogen base is replaced with another nitrogen
base.
Total number of bases in the sequence does not
change.
MISSENSE – amino acid does change
NONSENSE – amino acid is changed to a STOP
SILENT – amino acid does not change
Insertion
• An extra base is inserted into the sequence.
• The number of bases will increase
• This is also called a FRAMESHIFT
Deletion
• A base is removed or deleted from the
sequence.
• The number of bases will decrease.
• This is also called a FRAMESHIFT
Deletion
• A section of the chromosome is removed or
deleted.
• The chromosome becomes shorter.
• Smith Magenis Syndrome is an example
Duplication
• Sections of the chromosome are repeated or
copied.
• They have extra genetic material
• Oncogenes (genes linked to cancers such as
Breast, Ovarian, Colon Cancers) are the result
of duplication mutations
Inversion
• A portion of the chromosome has broken off,
turned upside down and reattached.
• The order of the genes and bases has been
changed.
• An inversion of Chromosome 9 is known to lead
to an increase in miscarriages or infertility.
• Most common inversion in humans.
Translocation
• A portion of one chromosome is transferred to
another chromosome
• Some cancers, infertility issues and Down
Syndrome (Trisomy 21) have been linked to
Translocation mutations.