1-27370659-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_003665.4(FCN3):c.595C>T(p.Arg199Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000316 in 1,614,114 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/21 in silico tools predict a benign 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. R199H) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000034 (0 hom.)
• Consequence: FCN3 NM_003665.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -1.13

Genes affected

FCN3 (HGNC:3625): (ficolin 3) Ficolins are a group of proteins which consist of a collagen-like domain and a fibrinogen-like domain. In human serum, there are two types of ficolins, both of which have lectin activity. The protein encoded by this gene is a thermolabile beta-2-macroglycoprotein found in all human serum and is a member of the ficolin/opsonin p35 lectin family. The protein, which was initially identified based on its reactivity with sera from patients with systemic lupus erythematosus, has been shown to have a calcium-independent lectin activity. The protein can activate the complement pathway in association with MASPs and sMAP, thereby aiding in host defense through the activation of the lectin pathway. Alternative splicing occurs at this locus and two variants, each encoding a distinct isoform, have been identified. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.3770868).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
FCN3	NM_003665.4	c.595C>T	p.Arg199Cys	missense_variant	7/8	ENST00000270879.9
FCN3	NM_173452.3	c.562C>T	p.Arg188Cys	missense_variant	6/7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
FCN3	ENST00000270879.9	c.595C>T	p.Arg199Cys	missense_variant	7/8	1	NM_003665.4	P2

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152222 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000654

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000398 AC: 10 AN: 251482 Hom.: 0 AF XY: 0.0000294 AC XY: 4 AN XY: 135914

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.000173

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.0000980

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000342 AC: 50 AN: 1461892 Hom.: 0 Cov.: 31 AF XY: 0.0000275 AC XY: 20 AN XY: 727246

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.000134

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000812

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000333

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152222 Hom.: 0 Cov.: 32 AF XY: 0.0000134 AC XY: 1 AN XY: 74364

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.0000654

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000329 Hom.: 0

Bravo AF: 0.0000340

ExAC AF: 0.0000412 AC: 5

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jul 08, 2022

The c.595C>T (p.R199C) alteration is located in exon 7 (coding exon 7) of the FCN3 gene. This alteration results from a C to T substitution at nucleotide position 595, causing the arginine (R) at amino acid position 199 to be replaced by a cysteine (C). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.13
BayesDel_addAF	Benign	-0.23	T
BayesDel_noAF	Benign	-0.29
Cadd	Benign	19
Dann	Uncertain	0.98
DEOGEN2	Benign	0.28	T;.
Eigen	Benign	-0.85
Eigen_PC	Benign	-1.0
FATHMM_MKL	Benign	0.013	N
LIST_S2	Benign	0.72	T;T
M_CAP	Benign	0.015	T
MetaRNN	Benign	0.38	T;T
MetaSVM	Benign	-0.79	T
MutationAssessor	Pathogenic	3.4	M;.
MutationTaster	Benign	1.0	N;N;N
PrimateAI	Benign	0.20	T
PROVEAN	Uncertain	-4.3	D;D
REVEL	Uncertain	0.30
Sift	Benign	0.070	T;T
Sift4G	Uncertain	0.0090	D;D
Polyphen		0.16	B;.
Vest4		0.37
MutPred		0.61		Gain of catalytic residue at L200 (P = 0.0186);.;
MVP		0.70
MPC		0.18
ClinPred		0.30	T
GERP RS		-2.6
Varity_R		0.36
gMVP		0.42

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: rs764351943; hg19: chr1-27697150;