Details Of Published TSH Receptor Mutation

Asp 633 Ala

c1898A>C

Constitutively Activating TSH Receptor Mutation

Type
gain
Manifestation
somatic
Exon
10
Molecular Characteristics:
default 
Clinical Features:
based on 1 hot nodule investigated by Parma et al. 1997 
Treatment:
default
Functional Characteristics:
cAMP
(basal)
cAMP
(TSH)
IP
(basal)
IP
(TSH)
TSH-Binding
Cell Surface Expression
Prevalence
LRA
Ref
3.3-4.4
1.3
n.d.
n.d.
nd
0.2-0.3
1
2,3
Legend:
cAMP (basal): basal in vitro cAMP production of mutant over wild-type TSHR
cAMP (TSH): maximal in vitro cAMP production of mutant over wild-type TSHR
IP (basal): basal in vitro IP production of mutant over wild-type TSHR
IP (TSH): maximal in vitro IP production of mutant over wild-type TSHR
TSH-binding: maximal TSH-binding compared to the wild-type TSHR
Cell surface expression: cell surface expression of mutant compared to WT-TSHR
LRA: linear regression analysis (LRA) of constitutive activity as a function of TSHR expression determined by 125I-bTSH binding or FACS analysis compared to the wild-type TSHR
Prevalence: Prevalence of (somatic and germline) activating mutations*
Ref: Reference for functional characterization
Child: Found in children.
Reference 1:
Parma et al.
J. Clin. Endocrinol. Metab. 82: 2695-2701
Diversity and prevalence of somatic mutations in the thyrotropin receptor and Gs alpha genes as a cause of toxic thyroid adenomas
1997
Reference 2:
Claeysen et al.
FEBS Lett 517: 195-200
A conserved Asn in TM7 of the thyrotropin receptor is a common requirement for activation by both mutations and its natural agonist.
2002
Reference 3:
Urizar et al.
J Biol Chem 280:17135-17141
An activation switch in the rhodopsin family of G protein-coupled receptors: the thyrotropin receptor.
2005