NM_001082971.2:c.1357C>T

Variant summary

Our verdict is Pathogenic. The variant received 17 ACMG points: 17P and 0B. PM1PM2PP2PP3_StrongPP5_Very_Strong

The NM_001082971.2(DDC):​c.1357C>T​(p.Arg453Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000142 in 1,614,122 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 Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R453H) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000015 ( 0 hom. )

Consequence

DDC
NM_001082971.2 missense

Scores

10
6
3

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:2

Conservation

PhyloP100: 7.46

Publications

7 publications found
Variant links:
Genes affected
DDC (HGNC:2719): (dopa decarboxylase) The encoded protein catalyzes the decarboxylation of L-3,4-dihydroxyphenylalanine (DOPA) to dopamine, L-5-hydroxytryptophan to serotonin and L-tryptophan to tryptamine. Defects in this gene are the cause of aromatic L-amino-acid decarboxylase deficiency (AADCD). AADCD deficiency is an inborn error in neurotransmitter metabolism that leads to combined serotonin and catecholamine deficiency. Multiple alternatively spliced transcript variants encoding different isoforms have been identified for this gene. [provided by RefSeq, Jun 2011]
DDC Gene-Disease associations (from GenCC):
  • aromatic L-amino acid decarboxylase deficiency
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, Ambry Genetics, Orphanet, Labcorp Genetics (formerly Invitae), G2P

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 17 ACMG points.

PM1
In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 5 uncertain in NM_001082971.2
PM2
Very rare variant in population databases, with high coverage;
PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 27 curated pathogenic missense variants (we use a threshold of 10). The gene has 8 curated benign missense variants. Gene score misZ: 0.40928 (below the threshold of 3.09). Trascript score misZ: 1.0771 (below the threshold of 3.09). GenCC associations: The gene is linked to aromatic L-amino acid decarboxylase deficiency.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.966
PP5
Variant 7-50463317-G-A is Pathogenic according to our data. Variant chr7-50463317-G-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 559481.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
DDCNM_001082971.2 linkc.1357C>T p.Arg453Cys missense_variant Exon 14 of 15 ENST00000444124.7 NP_001076440.2 P20711-1Q53Y41A0A0S2Z3N4

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
DDCENST00000444124.7 linkc.1357C>T p.Arg453Cys missense_variant Exon 14 of 15 1 NM_001082971.2 ENSP00000403644.2 P20711-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152234
Hom.:
0
Cov.:
32
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000159
AC:
4
AN:
251370
AF XY:
0.0000221
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:
0.0000352
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000150
AC:
22
AN:
1461888
Hom.:
0
Cov.:
32
AF XY:
0.0000151
AC XY:
11
AN XY:
727244
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000189
AC:
21
AN:
1112010
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.443
Heterozygous variant carriers
0
1
3
4
6
7
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:
0.00000657
AC:
1
AN:
152234
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74380
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41466
American (AMR)
AF:
0.00
AC:
0
AN:
15292
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5206
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10620
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68030
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.625
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000756
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.00
EpiControl
AF:
0.000119

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Deficiency of aromatic-L-amino-acid decarboxylase Pathogenic:2
May 20, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 453 of the DDC protein (p.Arg453Cys). This variant is present in population databases (rs142110773, gnomAD 0.004%). This missense change has been observed in individual(s) with clinical features of aromatic L-amino acid decarboxylase deficiency (PMID: 25597765). It has also been observed to segregate with disease in related individuals. For these reasons, this variant has been classified as Pathogenic. Experimental studies have shown that this missense change affects DDC function (PMID: 31953134). 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) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on DDC protein function. ClinVar contains an entry for this variant (Variation ID: 559481). This variant is also known as c.1123C>T (p.Arg375Cys). -

Jul 30, 2018
Medical Genetics Lab, Policlinico S. Orsola.Malpighi
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is extremely rare (only one allele in ExAC). The affected arginine is completely conserved across 98 vertebrates and the observed missense substitution was evaluated as deleterious by different prediction programs (Polyphen2, SIFT and MutationTaster). The variant was found in a homozygous state in three patients of one single family. Patients showed a phenotype that was compatible with AADC deficiency and abnormalities of neurotransmitters and their metabolites in one patient's CSF supported pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.22
BayesDel_addAF
Pathogenic
0.21
D
BayesDel_noAF
Pathogenic
0.18
CADD
Pathogenic
28
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.61
D;.;T;.;.;.;D
Eigen
Uncertain
0.64
Eigen_PC
Uncertain
0.49
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Pathogenic
0.99
.;D;D;D;.;D;D
M_CAP
Pathogenic
0.31
D
MetaRNN
Pathogenic
0.97
D;D;D;D;D;D;D
MetaSVM
Benign
-0.32
T
MutationAssessor
Pathogenic
3.3
M;.;.;.;.;.;M
PhyloP100
7.5
PrimateAI
Uncertain
0.58
T
PROVEAN
Uncertain
-4.2
D;.;.;.;D;D;D
REVEL
Pathogenic
0.81
Sift
Pathogenic
0.0
D;.;.;.;D;D;D
Sift4G
Uncertain
0.039
D;D;D;D;D;D;D
Polyphen
1.0
D;.;.;.;.;.;D
Vest4
0.94
MVP
0.78
MPC
1.1
ClinPred
0.99
D
GERP RS
5.4
Varity_R
0.67
gMVP
0.81
Mutation Taster
=5/95
disease causing (ClinVar)

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: rs142110773; hg19: chr7-50531015; COSMIC: COSV63565091; COSMIC: COSV63565091; API