What are gene mutations?

MYTUTOR SUBJECT ANSWERS

Answers / Biology / A Level / What are gene mutations?

733 views

What are gene mutations?

A mutation is any change to the base sequence of DNA.

The different types of mutations that can occur include:

Subsitution - this is where one base is swapped for another

Deletion - one or more bases are removed from the sequence

Insertion - one oe more bases are added to the sequence

Duplication - one or more bases are repeated

Inversion - a sequence of bases is reversed, for example if a sequence was ATAGC, then an inversion mutation would cause it to become CGATA

Mutations don't always necessarily cause changes to the primary structure as the amino acid code is degenerate (more than one base sequence codes for the same amino acid)

For example TAT and TAC both code for the amino acid Tyrosine, so if the T was substituted for a C it wouldn't make a difference to the primary structure.

However some mutations have a large effect on the base sequence. As the amino acid code is read in triplets, if a base is deleted or inserted it causes a frame shift, it changes the way the rest of the sequence is read.

Lauren G. A Level Biology tutor, A Level Maths tutor

3 years ago

Answered by Lauren, an A Level Biology tutor with MyTutor

Still stuck? Get one-to-one help from a personally interviewed subject specialist

220 SUBJECT SPECIALISTS

Xanthe W. GCSE Biology tutor, A Level Biology tutor, GCSE Maths tutor...

View profile

£24 /hr

Xanthe W.

Degree: Biological Sciences with a Year in Industry/Research (Bachelors) - Imperial College London University

Subjects offered:Biology, Maths+ 1 more

“Top tutor from the renowned Russell university group, ready to help you improve your grades.”

5.0

11 reviews | 60 completed tutorials

Save profile

Matthew C. GCSE Maths tutor, A Level Biology tutor, GCSE Biology tuto...

View profile

£20 /hr

Matthew C.

Degree: Medicine (Masters) - Bristol University

Subjects offered:Biology, Maths+ 3 more

“Hi! I'm a third year medical student at Bristol with lots of experience of tutoring for exams and helping people play the game of medical school admissions.”

5.0