Unit 2: Sources of genetic variation Flashcards
Mutation
An inherited change in genetic information
An inherited change in genetic information
Mutation
Mutations are a source of _______ and _______
genetic variation; diseases
How are mutations used to help in understanding basic biological processes? What is this technique called?
Studying mutations that disrupt normal processes often leads to the identification of genes that normally play a role in the process and can help in understanding the molecular details of a process. This technique is called genetic dissection.
Somatic mutations
Mutations which arise in somatic (body) tissues. It’s the basis for cancers.
germ-line mutation
Mutations that arise in cells that ultimately produce gametes
gene mutation
Mutations that arise within a single gene
base substitution
The simplest type of gene mutation that is the alteration of a single nucleotide in DNA
transition
A purine is replaced by another purine. Same for pyrimidines.
transversion
A purine is replaced by a pyrimidine or vice versa.
insertion
The addition of one or more nucleotide pairs
deletion
The removal of one or more nucleotide pairs
frameshift mutation
Changes in the reading frame of a gene
in-frame insertion/deletion
Mutations not affecting the reading frame. Consist of insertions or deletions occurring in multiples of three.
expanding nucleotide repeat
Mutations in which the number of copies of a set of nucleotides increases in number.