14-54902642-C-T

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 1P and 2B. PP2BP4_Moderate

The NM_000161.3(GCH1):​c.22G>A​(p.Ala8Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000148 in 1,483,118 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A8P) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000015 ( 0 hom. )

Consequence

GCH1
NM_000161.3 missense

Scores

2
1
15

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 0.443

Publications

2 publications found
Variant links:
Genes affected
GCH1 (HGNC:4193): (GTP cyclohydrolase 1) This gene encodes a member of the GTP cyclohydrolase family. The encoded protein is the first and rate-limiting enzyme in tetrahydrobiopterin (BH4) biosynthesis, catalyzing the conversion of GTP into 7,8-dihydroneopterin triphosphate. BH4 is an essential cofactor required by aromatic amino acid hydroxylases as well as nitric oxide synthases. Mutations in this gene are associated with malignant hyperphenylalaninemia and dopa-responsive dystonia. Several alternatively spliced transcript variants encoding different isoforms have been described; however, not all variants give rise to a functional enzyme. [provided by RefSeq, Jul 2008]
GCH1 Gene-Disease associations (from GenCC):
  • dystonia 5
    Inheritance: AD, AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, Orphanet, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), G2P
  • GTP cyclohydrolase I deficiency with hyperphenylalaninemia
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Orphanet, G2P
  • GTP cyclohydrolase I deficiency
    Inheritance: SD, AD Classification: DEFINITIVE Submitted by: ClinGen, Illumina

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -1 ACMG points.

PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 30 curated pathogenic missense variants (we use a threshold of 10). The gene has 1 curated benign missense variants. Gene score misZ: 1.5191 (below the threshold of 3.09). Trascript score misZ: 0.62455 (below the threshold of 3.09). GenCC associations: The gene is linked to GTP cyclohydrolase I deficiency, dystonia 5, GTP cyclohydrolase I deficiency with hyperphenylalaninemia.
BP4
Computational evidence support a benign effect (MetaRNN=0.17200258).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000161.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
GCH1
NM_000161.3
MANE Select
c.22G>Ap.Ala8Thr
missense
Exon 1 of 6NP_000152.1
GCH1
NM_001024024.2
c.22G>Ap.Ala8Thr
missense
Exon 1 of 7NP_001019195.1
GCH1
NM_001024070.2
c.22G>Ap.Ala8Thr
missense
Exon 1 of 7NP_001019241.1

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
GCH1
ENST00000491895.7
TSL:1 MANE Select
c.22G>Ap.Ala8Thr
missense
Exon 1 of 6ENSP00000419045.2
GCH1
ENST00000395514.5
TSL:1
c.22G>Ap.Ala8Thr
missense
Exon 1 of 7ENSP00000378890.1
GCH1
ENST00000543643.6
TSL:1
c.22G>Ap.Ala8Thr
missense
Exon 1 of 7ENSP00000444011.2

Frequencies

GnomAD3 genomes
AF:
0.0000132
AC:
2
AN:
152076
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000231
AC:
2
AN:
86518
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000628
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000150
AC:
20
AN:
1331042
Hom.:
0
Cov.:
32
AF XY:
0.0000152
AC XY:
10
AN XY:
655984
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
26792
American (AMR)
AF:
0.00
AC:
0
AN:
27778
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
23332
East Asian (EAS)
AF:
0.00
AC:
0
AN:
30020
South Asian (SAS)
AF:
0.00
AC:
0
AN:
72834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
37526
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
3930
European-Non Finnish (NFE)
AF:
0.0000180
AC:
19
AN:
1053774
Other (OTH)
AF:
0.0000182
AC:
1
AN:
55056
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.512
Heterozygous variant carriers
0
1
2
4
5
6
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000132
AC:
2
AN:
152076
Hom.:
0
Cov.:
33
AF XY:
0.0000135
AC XY:
1
AN XY:
74280
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41432
American (AMR)
AF:
0.00
AC:
0
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5166
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10610
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
314
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
67968
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000113

ClinVar

ClinVar submissions as Germline

Significance:Uncertain significance
Revision:criteria provided, multiple submitters, no conflicts
View on ClinVar
Pathogenic
VUS
Benign
Condition
-
1
-
GTP cyclohydrolase I deficiency;C1851920:Dystonia 5 (1)
-
1
-
Inborn genetic diseases (1)
-
1
-
not provided (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.080
BayesDel_addAF
Benign
-0.17
T
BayesDel_noAF
Benign
-0.31
CADD
Benign
11
DANN
Benign
0.79
DEOGEN2
Benign
0.35
T
Eigen
Benign
-1.3
Eigen_PC
Benign
-1.3
FATHMM_MKL
Benign
0.092
N
LIST_S2
Benign
0.60
T
M_CAP
Pathogenic
0.99
D
MetaRNN
Benign
0.17
T
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Benign
1.2
L
PhyloP100
0.44
PrimateAI
Uncertain
0.72
T
PROVEAN
Benign
-0.12
N
REVEL
Benign
0.27
Sift
Benign
0.56
T
Sift4G
Benign
0.62
T
Polyphen
0.0
B
Vest4
0.071
MutPred
0.29
Gain of phosphorylation at A8 (P = 6e-04)
MVP
0.46
MPC
1.0
ClinPred
0.024
T
GERP RS
1.2
PromoterAI
0.035
Neutral
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.053
gMVP
0.21
Mutation Taster
=98/2
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.0
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs529381971; hg19: chr14-55369360; API