chr19-6692971-C-T

Variant names:

• chr19-6692971-C-T
• rs121909585
• NM_000064.4:c.3343G>A

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM1 PM2 PP3_Strong

The NM_000064.4(C3):​c.3343G>A​(p.Asp1115Asn) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,858 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 (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: C3 NM_000064.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2 O:1
• Conservation: PhyloP100: 5.70

Genes affected

C3 (HGNC:1318): (complement C3) Complement component C3 plays a central role in the activation of complement system. Its activation is required for both classical and alternative complement activation pathways. The encoded preproprotein is proteolytically processed to generate alpha and beta subunits that form the mature protein, which is then further processed to generate numerous peptide products. The C3a peptide, also known as the C3a anaphylatoxin, modulates inflammation and possesses antimicrobial activity. Mutations in this gene are associated with atypical hemolytic uremic syndrome and age-related macular degeneration in human patients. [provided by RefSeq, Nov 2015]

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PM1: In a mutagenesis_site No effect on binding of C3d to CR2. (size 0) in uniprot entity CO3_HUMAN
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.942

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
C3	NM_000064.4	c.3343G>A	p.Asp1115Asn	missense_variant	Exon 26 of 41	ENST00000245907.11	NP_000055.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
C3	ENST00000245907.11	c.3343G>A	p.Asp1115Asn	missense_variant	Exon 26 of 41	1	NM_000064.4	ENSP00000245907.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461858 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 727238

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: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Atypical hemolytic-uremic syndrome with C3 anomaly Uncertain:1 Other:1

Dec 16, 2019

Baylor Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was determined to be of uncertain significance according to ACMG Guidelines, 2015 [PMID:25741868]. -

Dec 15, 2008

OMIM

Significance: risk factor

Review Status: no assertion criteria provided

Collection Method: literature only

- -

not provided Uncertain:1

Jul 12, 2022

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. Experimental studies have shown that this missense change affects C3 function (PMID: 18796626, 25608561). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). ClinVar contains an entry for this variant (Variation ID: 17062). This variant is also known as D1093N. This missense change has been observed in individual(s) with clinical features of atypical hemolytic uremic syndrome (PMID: 18796626, 25608561, 33456446, 34169201; Invitae). This variant is not present in population databases (gnomAD no frequency). This sequence change replaces aspartic acid, which is acidic and polar, with asparagine, which is neutral and polar, at codon 1115 of the C3 protein (p.Asp1115Asn). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.14
BayesDel_addAF	Benign	-0.21	T
BayesDel_noAF	Benign	-0.55
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Benign	0.34	T
Eigen	Uncertain	0.38
Eigen_PC	Uncertain	0.30
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Uncertain	0.97	D
M_CAP	Benign	0.050	D
MetaRNN	Pathogenic	0.94	D
MetaSVM	Benign	-0.81	T
MutationAssessor	Uncertain	2.1	M
PrimateAI	Uncertain	0.50	T
PROVEAN	Uncertain	-3.7	D
REVEL	Uncertain	0.36
Sift	Uncertain	0.026	D
Sift4G	Benign	0.11	T
Polyphen		1.0	D
Vest4		0.75
MutPred		0.80		Gain of methylation at K1113 (P = 0.0787);
MVP		0.68
MPC		1.2
ClinPred		0.99	D
GERP RS		4.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.70
gMVP		0.80

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

Other links and lift over

dbSNP: rs121909585; hg19: chr19-6692982; COSMIC: COSV55572808; COSMIC: COSV55572808;