chr19-6678012-A-C

Position:

• chr19-6678012-A-C

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM2 PP2 PP3_Moderate

The NM_000064.4(C3):​c.4862T>G​(p.Ile1621Ser) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,890 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, single submitter U:1
• Conservation: PhyloP100: 4.68

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.

• 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.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.928

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
C3	NM_000064.4	c.4862T>G	p.Ile1621Ser	missense_variant	41/41	ENST00000245907.11

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
C3	ENST00000245907.11	c.4862T>G	p.Ile1621Ser	missense_variant	41/41	1	NM_000064.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461890 Hom.: 0 Cov.: 35 AF XY: 0.00 AC XY: 0 AN XY: 727246

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: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

Jan 09, 2024

This sequence change replaces isoleucine, which is neutral and non-polar, with serine, which is neutral and polar, at codon 1621 of the C3 protein (p.Ile1621Ser). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with C3-related conditions. ClinVar contains an entry for this variant (Variation ID: 2085001). 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 C3 protein function. 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	Uncertain	0.54
BayesDel_addAF	Uncertain	0.055	T
BayesDel_noAF	Benign	-0.16
CADD	Benign	23
DANN	Uncertain	0.99
DEOGEN2	Benign	0.31	T
Eigen	Uncertain	0.49
Eigen_PC	Uncertain	0.38
FATHMM_MKL	Uncertain	0.91	D
LIST_S2	Benign	0.82	T
M_CAP	Pathogenic	0.45	D
MetaRNN	Pathogenic	0.93	D
MetaSVM	Benign	-0.70	T
MutationAssessor	Pathogenic	3.0	M
MutationTaster	Benign	0.98	D
PrimateAI	Uncertain	0.62	T
PROVEAN	Uncertain	-3.9	D
REVEL	Uncertain	0.34
Sift	Benign	0.049	D
Sift4G	Uncertain	0.0020	D
Polyphen		1.0	D
Vest4		0.63
MutPred		0.76		Loss of stability (P = 0.0171);
MVP		0.59
MPC		1.7
ClinPred		0.98	D
GERP RS		5.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.82
gMVP		0.93

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		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: chr19-6678023;