 Some genetic disorders can be caused by mutations › These mutations can occur within the DNA of a chromosome or they can occur to the chromosome its self

 (When a portion of the DNA is deleted or removed from the chromosome)  Example: › ATCGGCTA › CGGCTA  The “AT” fragment was deleted

Original: the fat cat ate the wee rat Deletion: the fat ate the wee rat  The sentence is missing a word › Still readable, however

Original: ATG CTA CAG GGA Deletion: ATG CAG GGA OOriginal strand: Met-Leu-Glu-Gly MMutated strand: Met-Glu-Gly

((When a portion of the chromosome is duplicated or repeated) EExample: ›T›T GACCATG ›T›T GACCATGTG TThe “TG” fragment was duplicated (or copied) at the end

Original: the fat cat ate the wee rat Insertion: the fat cat ate the the wee rat TThe sentence is still mostly readable

Original: ATG CTA CAG GGA Duplication: ATG CTA CAG CAG GGA OOriginal strand: Met-Leu-Glu-Gly MMutated strand: Met-Leu-Glu-Glu-Gly

 (When a portion of the DNA is inverted or switched around in the chromosome)  Example: › GTCATACCGT › GTTACACCGT  The “CAT” fragment flipped around to “TAC”

Original: the fat cat ate the wee rat Inversion: the fat tar eew eht eta tac TThe sentence is now almost completely unreadable

Original: ATG CTA CAG GGA Inversion: ATG AGG GAC ATC OOriginal strand: Met-Leu-Glu-Gly MMutated strand: Met-Arg-Asp-Iso

((When a portion of the DNA in the chromosome is replaced or substituted by a different base pair) EExample: ›G›G ATTACA ›G›G ATTGCA TThe “A” was replaced with a “G”

Original: the fat cat ate the wee rat Mutation: the fat hat ate the wee rat TThe substitution changed the meaning of the sentence, but it is still readable

Original: ATG CCG ATA GGA Substitution: ATG CCG CTA GGA OOriginal strand: Met-Pro-Iso-Gly MMutated strand: Met-Pro-Glu-Gly

((When a nitrogen base is inserted into the original strand of DNA) EExample: ›T›T AGCAT ›T›T AGCGAT NNote that an extra “G” was inserted

Original: the fat cat ate the wee rat Insertion: the fat cat xlw ate the wee rat TThe meaning of the sentence is still somewhat clear

Original: ATG CTA CAG GGA Insertion: ATG CTA TAG CAG GGA OOriginal strand: Met-Leu-Glu-Gly MMutated strand: Met-Leu-STOP

RRemember that these nitrogen bases code for amino acids ›T›The amino acids together make proteins OOne wrong letter can change all the amino acids after it

Original: the fat cat ate the wee rat Frame-Shift: the fat caa tet hew eer at TThe deletion of the “ t” completely changed the meaning of the sentence NNot only is the one word changed, every other word after i t is changed!

Original: ATG CTA CAG GGA TAA Frame-Shift: ATG CTC AGG GAT AA OOriginal strand: Met-Leu-Glu-Gly-Stop MMutated strand: Met-Leu-Arg-Asp

 What does a mutation in DNA actually change? › Changes a protein sequence! Bad Science!

 Everything still has to obey those pesky laws of physics! › No protein will give you telekinesis, flying, shooting lasers, growing super-huge and knowing ninjutsu, etc…

MMutations happen TThey happen with great regularity AAlmost all mutations are neutral OOf the remainder, benefit or harm depends on circumstances