Module 3 Types of mutations based on Phenotypic Effects Flashcards
give rise to altered forms. Also called visible
mutations (affect morphological traits)
Morphological mutations
result in nonviable organisms.
lethal mutations
gives a mutant phenotype under restrictive
conditions (environmental) and causes a wild-type phenotype under
permissive conditions.
Conditional mutation
ffect the function of proteins that can affect
the well-being and survival of the affected individual; result in the
inability to carry out a specific biochemical pathway
Biochemical mutations
can occur either in a protein-coding region or in any part of the genome, and whose effect on the genetic fitness of theorganism is negligible
Neutral mutations
mutations that affect the behavioral patterns of an organism
Behavioural mutations
reduces or eliminates the function of the gene product. Any type of mutation, from a point mutation to deletion of the entire gene, may lead to a loss of function. Mostly recessive, however a dominant effect of a loss-of-function mutation can occur during a situation known as haploinsufficiency.
Loss-of-function (null) mutations (LOF):
results in a gene product with enhanced or new functions. This may be due to a change in the amino acid sequence of the protein that confers a new activity, or it may result from a mutation in a regulatory region of the gene, leading to expression of the gene at higher levels, or the synthesis of the gene product at abnormal times, or places
Gain-of-function mutation (GOF)
those that affect the regulation of gene
expression by disrupting normal regulatory processes and inappropriately activating or inactivating expression of a gene; may also occur in regions such as splice junctions, promoters, or other regulatory regions of a gene that affect many aspects of gene regulation including transcription initiation, mRNA splicing, and mRNA stability.
Regulatory mutations
DNA sequences that appear to be highly susceptible to mutation
mutation hot spots: