What is a mutation???

GENETIC MUTATIONS

MISTAKES IN DNA

A MISTAKE CAN BE:

1. A point mutation – substitution, addition, or removal of a single DNA base.

2. A frameshift mutation – a point mutation due to an addition or deletion of a DNA base that causes a major change in the genetic code.

Sickle cell anemia is caused by a point mutation - substitution

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Muscular Dystrophy is caused by a frameshift mutation

THE CAT SAW THE DOG

CHANGE THE W TO A T:

THE CAT SAT THE DOG

CHANGE THE D TO AN H

THE CAT SAW THE HOG

MAJOR MISSENSE: REMOVE THE “C”

THE ATS AWT HED OGThis type of mutation causes a protein to be non-functional. It is a severe problem and can be lethal.

MAJOR MISSENCE: INSERT AN “M” after the first “The”.

THE MCA TSA WTH EDO G

The body cannot make sense out of the incorrect protein, just as the sentence no longer makes sense to you.

Nonsense• When a point mutation codes for a STOP in

the middle of a sequence. Could be due to any of the point mutations.

Nonfunctional dystrophin, the protein that helps attach your skeletal muscle to its surroundings.

Some mutations involve whole chromosomes:

1. Deletion: A piece of a chromosome is lost because of breakage during cell division

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Inversion: A piece of a chromosome breaks off and reattaches backwards.

The effect can be lethal.

Duplication: A portion of the chromosome is copied and placed

in the same chromosome.

Translocation: a piece of a chromosomes breaks off and

reattaches to a non-homologous chromosome

Non-disjunction: A chromosome fails to separate from its

homologue during meiosis

Turner’s Syndrome:

Klinefelter’s Syndrome:

Mutations in nature: