rs876661083

chr9-95150086-T-C

Variant summary

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

The NM_000136.3(FANCC):c.523A>G(p.Met175Val) variant causes a missense, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000342 in 1,461,844 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/23 in silico tools predict a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: FANCC NM_000136.3 missense, splice_region
• Scores: Splicing: ADA: 0.0006657
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:4
• Conservation: PhyloP100: 0.937

Genes affected

FANCC (HGNC:3584): (FA complementation group C) The Fanconi anemia complementation group (FANC) currently includes FANCA, FANCB, FANCC, FANCD1 (also called BRCA2), FANCD2, FANCE, FANCF, FANCG, FANCI, FANCJ (also called BRIP1), FANCL, FANCM and FANCN (also called PALB2). The previously defined group FANCH is the same as FANCA. Fanconi anemia is a genetically heterogeneous recessive disorder characterized by cytogenetic instability, hypersensitivity to DNA crosslinking agents, increased chromosomal breakage, and defective DNA repair. The members of the Fanconi anemia complementation group do not share sequence similarity; they are related by their assembly into a common nuclear protein complex. This gene encodes the protein for complementation group C. [provided by RefSeq, Jul 2008]

AOPEP (HGNC:1361): (aminopeptidase O (putative)) This gene encodes a member of the M1 zinc aminopeptidase family. The encoded protein is a zinc-dependent metallopeptidase that catalyzes the removal of an amino acid from the amino terminus of a protein or peptide. This protein may play a role in the generation of angiotensin IV. Alternate splicing results in multiple transcript variants. [provided by RefSeq, Oct 2010]

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=0.26974744).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
FANCC	NM_000136.3	c.523A>G	p.Met175Val	missense_variant, splice_region_variant	7/15	ENST00000289081.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
FANCC	ENST00000289081.8	c.523A>G	p.Met175Val	missense_variant, splice_region_variant	7/15	1	NM_000136.3	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251264 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135784

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000342 AC: 5 AN: 1461844 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 727220

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: 0.00000450

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000508 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Fanconi anemia Uncertain:2

Uncertain significance, no assertion criteria provided	clinical testing	Natera, Inc.	Dec 02, 2020	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Aug 30, 2021	This sequence change replaces methionine with valine at codon 175 of the FANCC protein (p.Met175Val). The methionine residue is moderately conserved and there is a small physicochemical difference between methionine and valine. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals affected with FANCC-related conditions. ClinVar contains an entry for this variant (Variation ID: 234556). Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated. 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. -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Feb 23, 2023

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge; This variant is associated with the following publications: (PMID: Gordon2000[Book]) -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 03, 2022

The p.M175V variant (also known as c.523A>G), located in coding exon 6 of the FANCC gene, results from an A to G substitution at nucleotide position 523. The methionine at codon 175 is replaced by valine, an amino acid with highly similar properties. This amino acid position is well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.15
BayesDel_addAF	Benign	-0.084	T
BayesDel_noAF	Benign	-0.36
Cadd	Benign	17
Dann	Benign	0.90
DEOGEN2	Benign	0.067	T;T;T
Eigen	Benign	0.016
Eigen_PC	Benign	0.026
FATHMM_MKL	Uncertain	0.89	D
M_CAP	Benign	0.011	T
MetaRNN	Benign	0.27	T;T;T
MetaSVM	Benign	-0.89	T
MutationAssessor	Uncertain	2.1	M;M;.
MutationTaster	Benign	0.58	N;N
PrimateAI	Benign	0.40	T
PROVEAN	Benign	-0.53	N;N;.
REVEL	Benign	0.23
Sift	Benign	0.36	T;T;.
Sift4G	Benign	0.20	T;T;T
Polyphen		0.80	P;P;.
Vest4		0.21
MutPred		0.70		Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);
MVP		0.69
MPC		0.11
ClinPred		0.22	T
GERP RS		4.8
Varity_R		0.14
gMVP		0.28

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.00067
dbscSNV1_RF	Benign	0.014
SpliceAI score (max)		0.010		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: rs876661083; hg19: chr9-97912368;