9-95171078-C-T

Variant names:

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_000136.3(FANCC):c.521+1G>A variant causes a splice donor, intron change. The variant allele was found at a frequency of 0.00000683 in 1,609,606 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000041 ( 0 hom. )

Consequence

FANCC
NM_000136.3 splice_donor, intron

Scores

Splicing: ADA: 1.000

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:9

Conservation

PhyloP100: 4.58

Variant links:

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]

FANCC links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 18 ACMG points.

PVS1

Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.

PM2

Very rare variant in population databases, with high coverage;

PP5

Variant 9-95171078-C-T is Pathogenic according to our data. Variant chr9-95171078-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 237074.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr9-95171078-C-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
FANCC	NM_000136.3 link	c.521+1G>A		splice_donor_variant, intron_variant	Intron 6 of 14	ENST00000289081.8	NP_000127.2	Q00597A0A024R9N2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
FANCC	ENST00000289081.8 link	c.521+1G>A		splice_donor_variant, intron_variant	Intron 6 of 14	1	NM_000136.3	ENSP00000289081.3		Q00597

Frequencies

GnomAD3 genomes

AF:

0.0000329

AC:

AN:

152174

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000121

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

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:

0.00000796

AC:

AN:

251136

Hom.:

AF XY:

0.00000737

AC XY:

AN XY:

135760

show subpopulations

Gnomad AFR exome

AF:

0.000123

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:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000412

AC:

AN:

1457432

Hom.:

Cov.:

AF XY:

0.00000276

AC XY:

AN XY:

725412

show subpopulations

Gnomad4 AFR exome

AF:

0.000180

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:

0.00

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000329

AC:

AN:

152174

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74350

show subpopulations

Gnomad4 AFR

AF:

0.000121

Gnomad4 AMR

AF:

0.00

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

Bravo

AF:

0.0000491

ESP6500AA

AF:

0.000227

AC:

ESP6500EA

AF:

0.00

AC:

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:9

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Fanconi anemia complementation group C

Pathogenic:4

May 12, 2022

Fulgent Genetics, Fulgent Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Dec 06, 2023

Baylor Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Feb 28, 2020

Leiden Open Variation Database

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: curation

Curator: Arleen D. Auerbach. Submitter to LOVD: Arleen D. Auerbach. -

Dec 21, 2022

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: FANCC c.521+1G>A is located in a canonical splice-site and is predicted to affect mRNA splicing resulting in a significantly altered protein due to either exon skipping, shortening, or inclusion of intronic material. Several computational tools predict a significant impact on normal splicing: Three predict the variant abolishes a 5' splicing donor site. However, these predictions have yet to be confirmed by functional studies. The variant allele was found at a frequency of 8e-06 in 251136 control chromosomes. c.521+1G>A has been reported in the literature in individuals affected with prostate or breast cancer (Antonarakis_2018, Lovejoy_2021), however, these reports do not provide unequivocal conclusions about association of the variant with Fanconi Anemia Group C. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Four clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 and classified the variant as pathogenic (n=1) and likely pathogenic (n=3). Based on the evidence outlined above, the variant was classified as likely pathogenic. -

Fanconi anemia

Pathogenic:2

Sep 11, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change affects a donor splice site in intron 6 of the FANCC gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in FANCC are known to be pathogenic (PMID: 17924555). This variant is present in population databases (rs145394391, gnomAD 0.01%). Disruption of this splice site has been observed in individual(s) with prostate cancer (PMID: 29439820). ClinVar contains an entry for this variant (Variation ID: 237074). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Jul 08, 2020

Natera, Inc.

Significance: Likely pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

FANCC-related disorder

Pathogenic:1

Feb 26, 2024

PreventionGenetics, part of Exact Sciences

Significance: Likely pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

The FANCC c.521+1G>A variant is predicted to disrupt the GT donor site and interfere with normal splicing. This variant was reported in an individual with prostate cancer (Antonarakis et al. 2018. PubMed ID: 29439820) and an individual with breast cancer (Lovejoy et al. 2021. PubMed ID: 33083949). To our knowledge, this variant has not been previously reported in the literature in association with Fanconi anemia. This variant is reported in 0.012% of alleles in individuals of African descent in gnomAD (http://gnomad.broadinstitute.org/variant/9-97933360-C-T) and is interpreted as pathogenic or likely pathogenic in ClinVar (https://www.ncbi.nlm.nih.gov/clinvar/variation/237074/). Variants that disrupt the consensus splice donor site in FANCC are expected to be pathogenic. This variant is interpreted as likely pathogenic. -

not provided

Pathogenic:1

May 26, 2023

GeneDx

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Canonical splice site variant predicted to result in a null allele in a gene for which loss of function is a known mechanism of disease; Not observed at significant frequency in large population cohorts (gnomAD); Also known as IVS5+1G>A; Observed in an individual with metastatic castration-resistant prostate cancer, and present only in controls in a case-control study of pancreatic cancer (Antonarakis et al., 2018; Hu et al., 2018); This variant is associated with the following publications: (PMID: 29922827, 31589614, 16199547, 17924555, 33083949, 29439820) -

Hereditary cancer-predisposing syndrome

Pathogenic:1

Jun 06, 2023

Ambry Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.521+1G>A intronic variant results from a G to A substitution one nucleotide after coding exon 5 of the FANCC gene. One study detected this alteration in 0/3030 pancreatic cancer cases and 2/123136 population controls (Hu C et al. JAMA, 2018 06;319:2401-2409). This alteration has also been detected in individuals diagnosed with breast and metastatic prostate cancer (Lovejoy LA et al. Fam Cancer, 2021 07;20:181-187; Antonarakis ES et al. Eur Urol, 2018 08;74:218-225). This nucleotide position is highly conserved in available vertebrate species. In silico splice site analysis predicts that this alteration will weaken the native splice donor site; however, direct evidence is insufficient at this time (Ambry internal data). Alterations that disrupt the canonical splice site are expected to cause aberrant splicing, resulting in an abnormal protein or a transcript that is subject to nonsense-mediated mRNA decay. As such, this alteration is classified as likely pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.45

BayesDel_noAF

Pathogenic

0.30

CADD

Pathogenic

DANN

Uncertain

0.99

Eigen

Pathogenic

1.1

Eigen_PC

Pathogenic

0.95

FATHMM_MKL

Uncertain

0.89

GERP RS

5.1

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Pathogenic

1.0

dbscSNV1_RF

Pathogenic

0.94

SpliceAI score (max)

0.98

Details are displayed if max score is > 0.2

DS_DL_spliceai

0.98

Position offset: 1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over