Mutations
description
Transcript of Mutations
Gene mutation is the change in the order of the A,G,C,T bases in a gene
These altered genes can have a positive, negative or no effect on the organism
Frameshift mutation-The addition or deletion of a single nucleotide
Point mutation-The substitution of a single nucleotide
Transposon-Jumping genes
Chromosomal Abnormality (not a gene mutation)-insertion, deletion, duplication, inversion, translocation
Deletion- One base is missingThe Gene should be ACTGCGTBut instead is ACGCGT
Addition- One extra base is addedThe Gene should be ACTGCGTBut instead is ACTGTCGT
Nonsense- One base change results in a stop codon being created. Created truncated polypeptide
Ex) UGA, UAA, UAG
Muscular dystrophy…dystrophin protein not produced
Cystic fibrosis regulatory gene
Missense- Base substituted changes one amino in the polypeptide. Different protein is created. Function of protein is changed
For example, sickle-cell disease is caused by a single point in the beta-hemoglobin gene that converts a GAG codon into GUG, which encodes the amino acid valine rather than glutamic acid.
Neutral- Base substituted changes the amino acid. Different protein is created. Function of protein is not changed
Silent- Base substituted but the amino acid does not change.
Ie) the new codon codes for the same amino acid
Protein will be the same.
There are 64 codon variations and only 20 AA
Ex) UUU and UUC both code for Phenylalanine
Barbara McClintock was awarded the Nobel Prize for discovering genes can move and turned on/off
Insertion, deletion, duplication, inversion, translocation
This is the usual appearance of the pepper moth. It blends right in with its surroundings to avoid being eaten.
However, factories in an area polluted and the trees became a blackish color
As a result of a mutation, a black version of the pepper moth is now better suited
The mutation of a gene has a positive impact on the organism
Ex) Mutated gene that creates a protein that prevents HIV from infecting the organism
Small changes in certain genes have harmful affects on the organism
Ex) Sickle cell anemia
The mutation has no impact on the organism Ex) Spirit Bear
Substances or factors that cause mutation in DNA
Ex) UV Light, x-rays, pollutants and other harmful chemicals
Gene Therapy- replace a mutated gene with a healthy copyComplicated and highly experimental
Spider-tailed Viper- Iran
Squid Camo...4:24
Mimic Octopus
Lyre Bird