Genetics 2 Flashcards
Genetic Effects of Duplication
a. unequal crossing over
b. production of distinct phenotypes
types of mutation
change in chromosome structure
change in chromosome number
gene mutation
involves a rotation of a part of a chromosome or a set of genes by 180degrees on its own axis
Inversion
terminal section of chromosome is absent; involves only 1 break on the chromosome
terminal deletion
the centromere is included in the inversion
pericentric inversion
Change in Chromosome Structure
Occurs in two mechanisms:
a. breakage and re-joining
b. crossing-over between segments of repetitive DNA.
Gene Mutations based on Molecular Change
-Microlesions
-Frameshift mutations
Types of translocation
-Reciprocal translocation
-Non-reciprocal translocation
-Shift or intercalary translocation
mutation that affect only the individual that carries them.
Somatic mutations
loss of a chromosome segment
Deficiencies or deletions
DNA sequences that appear to be highly susceptible to mutation
mutation hot spots
Types of Chromosomal Aberrations
- Deficiencies or deletions
- Duplication or repeats
- Inversion
d. Translocation
intermediate section of chromosome is lost; involves 2 breaks, one on each end of the deleted region.
Interstitial or intercalary deletion
base-pair substitution or point mutations
Microlesions
caused by deletion or insertion of 1 or more
nucleotides into the original DNA sequence
Frameshift mutations