rs1353623780

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM1PM2PP3_ModeratePP5

The NM_000161.3(GCH1):​c.400G>A​(p.Asp134Asn) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000693 in 1,443,062 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 6.9e-7 ( 0 hom. )

Consequence

GCH1
NM_000161.3 missense

Scores

7
9
3

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2U:1

Conservation

PhyloP100: 7.76
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

PM1
In a chain GTP cyclohydrolase 1 (size 249) in uniprot entity GCH1_HUMAN there are 25 pathogenic changes around while only 3 benign (89%) in NM_000161.3
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.923
PP5
Variant 14-54865380-C-T is Pathogenic according to our data. Variant chr14-54865380-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 459899.We mark this variant Likely_pathogenic, oryginal submissions are: {Uncertain_significance=1, Likely_pathogenic=2}.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
GCH1NM_000161.3 linkuse as main transcriptc.400G>A p.Asp134Asn missense_variant 2/6 ENST00000491895.7 NP_000152.1 P30793-1A0A024R642

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
GCH1ENST00000491895.7 linkuse as main transcriptc.400G>A p.Asp134Asn missense_variant 2/61 NM_000161.3 ENSP00000419045.2 P30793-1

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD3 exomes
AF:
0.00000399
AC:
1
AN:
250832
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
135632
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 SAS exome
AF:
0.0000327
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
6.93e-7
AC:
1
AN:
1443062
Hom.:
0
Cov.:
26
AF XY:
0.00
AC XY:
0
AN XY:
719286
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.0000117
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
Cov.:
32

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:2Uncertain:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Pathogenic:1Uncertain:1
Likely pathogenic, criteria provided, single submitterclinical testingCeGaT Center for Human Genetics TuebingenMar 01, 2019- -
Uncertain significance, criteria provided, single submitterclinical testingGeneDxMar 03, 2023Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 33903016, 17898029) -
GTP cyclohydrolase I deficiency;C1851920:Dystonia 5 Pathogenic:1
Likely pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpAug 24, 2023In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. This variant disrupts the p.Asp134 amino acid residue in GCH1. Other variant(s) that disrupt this residue have been observed in individuals with GCH1-related conditions (PMID: 7874165), which suggests that this may be a clinically significant amino acid residue. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt GCH1 protein function. ClinVar contains an entry for this variant (Variation ID: 459899). This missense change has been observed in individuals with autosomal dominant or autosomal recessive dopa-responsive dystonia (PMID: 17898029; Invitae). This variant is present in population databases (no rsID available, gnomAD 0.003%). This sequence change replaces aspartic acid, which is acidic and polar, with asparagine, which is neutral and polar, at codon 134 of the GCH1 protein (p.Asp134Asn). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.47
BayesDel_addAF
Uncertain
0.065
T
BayesDel_noAF
Uncertain
-0.040
CADD
Uncertain
26
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.91
D;D;.;D;.
Eigen
Uncertain
0.33
Eigen_PC
Uncertain
0.46
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Uncertain
0.96
.;D;D;.;D
M_CAP
Uncertain
0.12
D
MetaRNN
Pathogenic
0.92
D;D;D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Benign
1.7
L;L;L;L;L
PrimateAI
Pathogenic
0.89
D
PROVEAN
Pathogenic
-4.4
.;D;D;D;D
REVEL
Pathogenic
0.66
Sift
Benign
0.068
.;T;T;T;T
Sift4G
Uncertain
0.038
D;D;D;D;D
Polyphen
0.091
B;B;B;B;P
Vest4
0.91
MutPred
0.93
Gain of ubiquitination at K133 (P = 0.0741);Gain of ubiquitination at K133 (P = 0.0741);Gain of ubiquitination at K133 (P = 0.0741);Gain of ubiquitination at K133 (P = 0.0741);Gain of ubiquitination at K133 (P = 0.0741);
MVP
0.83
MPC
1.2
ClinPred
0.96
D
GERP RS
5.4
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.67
gMVP
0.98

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs1353623780; hg19: chr14-55332098; API