MUTATIONS A permanent alteration to the chromosome structure

  • Slides: 12
Download presentation
MUTATIONS: A permanent alteration to the chromosome structure or nucleotide sequence of an organism’s

MUTATIONS: A permanent alteration to the chromosome structure or nucleotide sequence of an organism’s genome.

Source of Mutations • Mutations and chromosomal damage can occur from the following sources:

Source of Mutations • Mutations and chromosomal damage can occur from the following sources: I. Mutagens: Chemicals that cause mutations or damage in DNA (eg. Nitrous Acid, Ethidium bromide) II. Radiation: Ionizing radiation such as X-Rays, UV Rays and Gamma Rays can damage DNA III. Clastogens: Chemicals that damage or break chromosomes (eg. Benzene, Arsenic). The universal pictogram for something being mutagenic or carcinogenic

Chromosomal Mutations • These can include: Ø Deletions: Part of the chromosome is deleted

Chromosomal Mutations • These can include: Ø Deletions: Part of the chromosome is deleted (eg: Wolf-Hirschhorn Syndrome) Ø Insertions: Part of a different chromosome is inserted (eg: not typically deleterious unless it breaks up a gene) Ø Duplications: A portion of a chromosome is duplicated (eg: Charcot-Marie-Tooth Disease) Ø Translocations: A portion of one chromosome is transferred to another chromosome (eg: usually has no effect unless it breaks up a gene). Ø Inversion: A portion of one chromosome has broken off, turned upside down and reattached- the sequence is inverted (eg: Not considered to have much of an effect)

Point Mutations A mutation in which a single pair of nucleotides in a certain

Point Mutations A mutation in which a single pair of nucleotides in a certain point in the gene sequence is affected. 3 Types: I. II. Substitution: Substituting one base for another. Insertion: Inserting a new base into the sequence. III. Deletion: Deleting an existing base from the sequence. ou y o d Which ill have w think fect f e t s a the le on an m? is organ

Effects of Point Mutations can have one of three outcomes: Silent Mutations: No noticeable

Effects of Point Mutations can have one of three outcomes: Silent Mutations: No noticeable effect on the protein. The mutated codon codes for the same amino acid as the original codon or the different amino acid has no effect on the structure of the protein (and ultimately the phenotype of the organism). I.

Effects of Point Mutations can have one of three outcomes: Missense: The mutation alters

Effects of Point Mutations can have one of three outcomes: Missense: The mutation alters the amino acid the original codon coded for, affecting the shape and function of the protein. I. The amino acid sequence makes sense (can be constructed into a protein), just not the right sense.

Effects of Point Mutations can have one of three outcomes: Nonsense: The mutation alters

Effects of Point Mutations can have one of three outcomes: Nonsense: The mutation alters the original codon for an amino-acid into a STOP codon, terminating the polypeptide chain prematurely. I. The amino acid sequence no longer makes any sense. These are the most impactfulas they usually make the protein unusable.

Effects of Point Mutations

Effects of Point Mutations

Somatic vs. Gamete Mutations For a mutation to be inherited and therefore accumulate in

Somatic vs. Gamete Mutations For a mutation to be inherited and therefore accumulate in a gene pool (which is the driving force behind evolution), the mutation must happen in a gamete (sperm or egg cell). Mutations occurring in somatic (body) cells can affect the cell in question (and can still be seriousthink CANCER!), but can not be passed on to offspring.

Effects of Radiation Vertus Hardiman: • https: //en. wikipedia. org/wiki/Vertus_Hardiman • https: //youtu. be/78

Effects of Radiation Vertus Hardiman: • https: //en. wikipedia. org/wiki/Vertus_Hardiman • https: //youtu. be/78 n. FY_Xb. Jz. E Video contains some graphic images

Effects of Radiation Hirsoshima Videos have graphic images: https: //youtu. be/iq. G 35 Tpgk.

Effects of Radiation Hirsoshima Videos have graphic images: https: //youtu. be/iq. G 35 Tpgk. IM Particulary 3: 45 -10: 10 (https: //youtu. be/jhigykrq. MMM)

Effects of Radiation Chernobyl 5 Facts about Chernobyl: https: //youtu. be/2 VYQ 3 CBpz.

Effects of Radiation Chernobyl 5 Facts about Chernobyl: https: //youtu. be/2 VYQ 3 CBpz. UQ A walk around Chernobyl today: https: //youtu. be/9 DWnjc. So 9 J 0

Chromosome Structure and Mutations Genetics Chromosome Mutations IncludeChromosome Structure and Mutations Genetics Chromosome Mutations Include
Types of Chromosome Mutations Chromosome Mutations Deletion DeficiencyTypes of Chromosome Mutations Chromosome Mutations Deletion Deficiency
Types of Chromosome Mutations Chromosome Mutations Deletion DeficiencyTypes of Chromosome Mutations Chromosome Mutations Deletion Deficiency
Types of Chromosome Mutations Chromosome Mutations Changes inTypes of Chromosome Mutations Chromosome Mutations Changes in
Types of Chromosome Mutations Chromosome Mutations Deletion DeficiencyTypes of Chromosome Mutations Chromosome Mutations Deletion Deficiency
ChromosomesDNA Mutations Chromosome Mutation n Mutations are permanentChromosomesDNA Mutations Chromosome Mutation n Mutations are permanent
MUTATION SPONTANEOUS MUTATIONS INDUCED MUTATIONS MUTATIONS Mutations areMUTATION SPONTANEOUS MUTATIONS INDUCED MUTATIONS MUTATIONS Mutations are
Mutations Mutations overview Smallscale mutations Missense mutations NonsenseMutations Mutations overview Smallscale mutations Missense mutations Nonsense
Mutations Mutations Types of Mutations Point Mutations occursMutations Mutations Types of Mutations Point Mutations occurs
Chromosome and its Structure Chromosome Chromosome means chromaChromosome and its Structure Chromosome Chromosome means chroma
MUTATIONS MUTATIONS The alteration of an organisms DNAMUTATIONS MUTATIONS The alteration of an organisms DNA