Mutations Flashcards
What is a mutation?
Spontaneous change in the DNA base sequence
Can affect genes and therefore the proteins they code for
What are the 5 main types of mutation?
Deletion Duplication Inversion Translocation Substitution
What is a deletion mutation?
Removing base/s
Frame shift (to the left)
What is a Duplication mutation?
Repeating bases
What is an inversion mutation?
DNA segment reversed
Paracentric - outside centromere
Pericentric - include centromere
What is a translocation mutation?
Exchange with non homologous chromosome
What are the 2 types of substitution mutations and what do they code for?
Missense - change causes new AA to be coded for Eg. HbA to HbS
Nonsense- change causes premature stop codon forming
What are the 3 things mutations can be?
Polymorphisms (non pathogenic, no change)
Gene pathogenic, affects gene products (proteins)
Whole chromosomes, numerical and structural changes
What does the karyotype show?
The number and appearance of chromosomes in a cell
What does an ideogram show?
Shows distinctive banding of chromosomes