Chemicals and radiation (UV, ionizing).
C. II and III
A mutation that disrupts the function of the gene product.
Regulatory changes affect how quickly a protein is degraded.
A splice acceptor site mutation can result in exon skipping.
Potentially minor impact.
Mutations can affect an organism's fitness by altering traits that influence survival and reproduction, potentially leading to advantages, disadvantages, or neutral effects.
No, many repair mechanisms exist, but not all are perfect.
There will be no changes.
The loss of odorant receptors helped switch to herbivory.
Loss-of-function mutations are more likely than gain-of-function mutations.
The common sequence for the splice donor site is GU, and for the splice acceptor site is AG.
Mutations can alter the sequence of DNA, potentially leading to changes in the mRNA and the resulting protein, which can affect the protein's function.
Fitness impact varies depending on the mutation.
A mutation at the start codon could affect splicing, potentially splicing out the exon entirely or not splicing at all.
A mutation that improves, increases, or innovates the function of the gene product.
LOF (Loss-of-Function) and GOF (Gain-of-Function) describe the effects on gene activity and product, not cellular or organismal phenotype.
All of the above
Silent mutation
Frameshift mutation
A mutation where a codon changes but still codes for the same amino acid, e.g., AAG (Lys) -> AAA (Lys).
Imperfect DNA repair can lead to permanent changes to the DNA, i.e. mutations.
An insertion mutation involves the addition of one or more nucleotide base pairs into a DNA sequence.
They change the expression (when, where, how much).
In Scenario 1, when the splice acceptor site is mutated, the exon is skipped.
Missense mutation (same charge)
Potentially significant impact.
A mutation where a codon changes and codes for a different amino acid, e.g., UUU (Phe) -> UCU (Ser).
A duplication mutation occurs when a segment of DNA is copied and inserted into the genome, resulting in multiple copies of that segment.
Mutations in introns can have no effect, change expression if they act as enhancers/promoters, or alter splicing if they affect splice sites.
Malignant migrating partial seizures of infancy is an example of a condition associated with Gain-of-Function mutations.
A splice donor site mutation can lead to the retention of the intron.
The main types of mutations include point mutations, insertions, deletions, and chromosomal rearrangements.
Likely severe impact.
A deletion mutation is the loss of one or more nucleotide base pairs from a DNA sequence.
They change mRNA stability and localization.
Minimal to no impact.
Nonsense mutation 1 (closer to the start of the gene)
A mutation caused by insertions or deletions that change the reading frame of the codons, e.g., AAG UAC UCU AAG CCA GGC UAA (Lys-Tyr-Ser-Lys-Pro-Gly) -> AAG UAC CUC UAA GCC AGG CUA A (Lys-Tyr-Leu).
C. II and III
An inversion mutation involves a segment of DNA being reversed end to end, effectively flipping the sequence within the genome.
GOF stands for Gain-of-Function. It is a source of novelty, but new is not always good.
The deletion created a frameshift
Common sources of mutations include errors during DNA replication, exposure to mutagens such as UV light and chemicals, and viral infections.
Nonsense mutation 2 occurs later in the gene, so the protein is mostly made and thus may still retain some function.
Redundancy in the gene and protection in mutations.
A promoter mutation will affect how the gene is regulated, thus it will not change the protein sequence.
A translocation mutation involves segments of DNA being rearranged between different chromosomes or within the same chromosome, leading to a change in the position of the genetic material.
Two examples of Gain-of-Function mutations are increased protein activity and ectopic expression.
The deletion decreased the size of the protein
Nonsense mutation
Likely severe impact.
A point mutation or substitution is a type of mutation where a single nucleotide base is changed, inserted, or deleted from a sequence of DNA or RNA.
Because it is easier to break something than to make something new.
GOF mutation
In Scenario 2, when the splice donor site is mutated, the intron is retained.
Missense mutation (different charge)
Phenotypic consequences of mutations can range from no visible effect to significant changes in physical traits or metabolic functions, depending on the mutation's nature and location.
A mutation where a codon changes to a stop codon, e.g., UAC (Tyr) -> UAA (stop).
