rs138149179

Variant names:

• chr13-100273218-C-G
• rs138149179
• NM_000282.4:c.937C>G

Your query was ambiguous. Multiple possible variants found:

• chr13-100273218-C-G
• chr13-100273218-C-T

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM1 PM2 PP3_Strong

The NM_000282.4(PCCA):​c.937C>G​(p.Arg313Gly) variant causes a missense change. The variant allele was found at a frequency of 0.000000685 in 1,460,856 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 Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R313Q) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: PCCA NM_000282.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 4.74
• Publications: 13 publications found

Genes affected

PCCA (HGNC:8653): (propionyl-CoA carboxylase subunit alpha) The protein encoded by this gene is the alpha subunit of the heterodimeric mitochondrial enzyme Propionyl-CoA carboxylase. PCCA encodes the biotin-binding region of this enzyme. Mutations in either PCCA or PCCB (encoding the beta subunit) lead to an enzyme deficiency resulting in propionic acidemia. Multiple transcript variants encoding different isoforms have been found for this gene.[provided by RefSeq, May 2010]

PCCA Gene-Disease associations (from GenCC):

• propionic acidemia

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Labcorp Genetics (formerly Invitae), Myriad Women’s Health, ClinGen, Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 8 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 11 uncertain in NM_000282.4
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.99

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PCCA	NM_000282.4	c.937C>G	p.Arg313Gly	missense_variant	Exon 12 of 24	ENST00000376285.6	NP_000273.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PCCA	ENST00000376285.6	c.937C>G	p.Arg313Gly	missense_variant	Exon 12 of 24	1	NM_000282.4	ENSP00000365462.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460856 Hom.: 0 Cov.: 29 AF XY: 0.00000138 AC XY: 1 AN XY: 726762

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.0000299 AC: 1 AN: 33460

American (AMR) AF: 0.00 AC: 0 AN: 44710

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26116

East Asian (EAS) AF: 0.00 AC: 0 AN: 39672

South Asian (SAS) AF: 0.00 AC: 0 AN: 86226

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53412

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

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111134

Other (OTH) AF: 0.00 AC: 0 AN: 60358

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000756

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Propionic acidemia Uncertain:1

Apr 04, 2021

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. 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 expected to disrupt PCCA protein function. This variant has not been reported in the literature in individuals with PCCA-related conditions. This variant is not present in population databases (ExAC no frequency). This sequence change replaces arginine with glycine at codon 313 of the PCCA protein (p.Arg313Gly). The arginine residue is highly conserved and there is a moderate physicochemical difference between arginine and glycine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.93
BayesDel_addAF	Pathogenic	0.56	D
BayesDel_noAF	Pathogenic	0.57
CADD	Pathogenic	26
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.99	.;.;D
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.87
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Pathogenic	0.98	D;D;D
M_CAP	Pathogenic	0.55	D
MetaRNN	Pathogenic	0.99	D;D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	4.9	.;H;H
PhyloP100		4.7
PrimateAI	Uncertain	0.68	T
PROVEAN	Pathogenic	-6.5	D;D;D
REVEL	Pathogenic	0.92
Sift	Pathogenic	0.0	D;D;D
Sift4G	Uncertain	0.0030	D;D;D
Polyphen		1.0	D;.;D
Vest4		0.95
MutPred		0.92		.;Loss of MoRF binding (P = 0.0953);Loss of MoRF binding (P = 0.0953);
MVP		0.99
MPC		0.71
ClinPred		1.0	D
GERP RS		4.7
Varity_R		0.98
gMVP		0.93
Mutation Taster		=20/80	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: rs138149179; hg19: chr13-100925472; COSMIC: COSV104692195;