Tutorial 2 - Nomenclature

Question 1

What does each of the letter prefixes in HGVS nomenclature stand for?
g
c
n
r
p

Answer 1

genomic
coding
non-coding
RNA 
protein

Question 2

What are the key parts of a mutation written in HGVS nomenclature?

Answer 2

Reference sequence

Letter prefix

Question 3

Which reference sequence would you use if referring to

• a complete genomic molecule
• an incomplete genomic molecule
• an mRNA transcript
• a protein

Answer 3

NC
NG
NM
NP

Question 4

Describe what this mutation written in HGVS nomenclature is showing
NM_004006.2:c.93+1G>A

Answer 4

Reference sequence in an mRNA transcript
Coding region
At point 93+1
A guanine has mutated to adenine

Question 5

What are the 6 types of protein mutations?

Answer 5

Synonymous
Mis-sense
Nonsense 
Frameshift
In-frame duplication 
Intronic

Question 6

Advantages of Star allele nomenclature

Answer 6

Faster and easier to write down
Clinicians less likely to make mistakes
Single star can represent many variants

Question 7

Disadvantages of Star allele nomenclature

Answer 7

Makes interpretation of results difficult