19-6677887-T-C

Position:

• chr19-6677887-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM1 PM2 PP2

The NM_000064.4(C3):​c.4987A>G​(p.Asn1663Asp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: C3 NM_000064.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.94

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 Uncertain_significance. Variant got 5 ACMG points.

• PM1: In a site Coordinates Mg2+ for interaction with Complement factor B Bb fragment (size 0) in uniprot entity CO3_HUMAN
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), C3. . Gene score misZ 2.7489 (greater than the threshold 3.09). Trascript score misZ 4.431 (greater than threshold 3.09). GenCC has associacion of gene with complement component 3 deficiency, C3 glomerulonephritis, atypical hemolytic-uremic syndrome with C3 anomaly.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
C3	NM_000064.4	c.4987A>G	p.Asn1663Asp	missense_variant	41/41	ENST00000245907.11	NP_000055.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
C3	ENST00000245907.11	c.4987A>G	p.Asn1663Asp	missense_variant	41/41	1	NM_000064.4	ENSP00000245907	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 01, 2022

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: "Probably Damaging"; Align-GVGD: "Class C0"). This variant has not been reported in the literature in individuals affected with C3-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces asparagine, which is neutral and polar, with aspartic acid, which is acidic and polar, at codon 1663 of the C3 protein (p.Asn1663Asp). 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.22
BayesDel_addAF	Benign	-0.13	T
BayesDel_noAF	Benign	-0.43
CADD	Benign	23
DANN	Uncertain	1.0
DEOGEN2	Benign	0.26	T
Eigen	Benign	0.19
Eigen_PC	Benign	0.095
FATHMM_MKL	Uncertain	0.91	D
LIST_S2	Benign	0.78	T
M_CAP	Pathogenic	0.43	D
MetaRNN	Uncertain	0.55	D
MetaSVM	Benign	-0.45	T
MutationAssessor	Pathogenic	3.4	M
MutationTaster	Benign	0.52	N
PrimateAI	Uncertain	0.67	T
PROVEAN	Uncertain	-2.6	D
REVEL	Benign	0.18
Sift	Uncertain	0.017	D
Sift4G	Uncertain	0.019	D
Polyphen		1.0	D
Vest4		0.25
MutPred		0.42		Gain of stability (P = 0.0068);
MVP		0.54
MPC		1.6
ClinPred		0.98	D
GERP RS		4.1
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.70
gMVP		0.72

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr19-6677898;