7-50537920-C-G

Variant names:

• chr7-50537920-C-G
• rs201797574
• NM_001082971.2:c.375G>C

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM1 PM2 PP2 PP3

The NM_001082971.2(DDC):​c.375G>C​(p.Met125Ile) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,864 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: DDC NM_001082971.2 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 6.12
• Publications: 0 publications found

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-AS1 (HGNC:40171): (DDC antisense RNA 1)

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 6 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, 0.782

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001082971.2. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	DDC	NM_001082971.2	MANE Select	c.375G>C	p.Met125Ile	missense	Exon 4 of 15	NP_001076440.2	A0A0S2Z3N4
	DDC	NM_000790.4		c.375G>C	p.Met125Ile	missense	Exon 4 of 15	NP_000781.2	P20711-1
	DDC	NM_001242886.2		c.261G>C	p.Met87Ile	missense	Exon 3 of 14	NP_001229815.2	A0A087WV24

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	DDC	ENST00000444124.7	TSL:1 MANE Select	c.375G>C	p.Met125Ile	missense	Exon 4 of 15	ENSP00000403644.2	P20711-1
	DDC	ENST00000357936.9	TSL:1	c.375G>C	p.Met125Ile	missense	Exon 4 of 15	ENSP00000350616.5	P20711-1
	DDC	ENST00000380984.4	TSL:1	c.375G>C	p.Met125Ile	missense	Exon 4 of 10	ENSP00000370371.4	P20711-2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461864 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 727234

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

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: 53408

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111998

Other (OTH) AF: 0.00 AC: 0 AN: 60394

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.74
BayesDel_addAF	Uncertain	0.14	D
BayesDel_noAF	Uncertain	-0.040
CADD	Uncertain	23
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.54	D
Eigen	Uncertain	0.54
Eigen_PC	Uncertain	0.59
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Pathogenic	0.99	D
M_CAP	Benign	0.077	D
MetaRNN	Pathogenic	0.78	D
MetaSVM	Benign	-0.84	T
MutationAssessor	Uncertain	2.8	M
PhyloP100		6.1
PrimateAI	Uncertain	0.72	T
PROVEAN	Uncertain	-3.1	D
REVEL	Uncertain	0.42
Sift	Uncertain	0.023	D
Sift4G	Benign	0.083	T
Polyphen		0.80	P
Vest4		0.69
MutPred		0.71		Loss of ubiquitination at K130 (P = 0.0503)
MVP		0.60
MPC		1.0
ClinPred		0.96	D
GERP RS		5.6
Varity_R		0.87
gMVP		0.93
Mutation Taster		=31/69	disease causing

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

Other links and lift over

dbSNP: rs201797574; hg19: chr7-50605618;