NM_000136.3:c.843+5G>A

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM2PP3_ModeratePP5

The NM_000136.3(FANCC):​c.843+5G>A variant causes a splice region, intron change. The variant allele was found at a frequency of 0.0000688 in 1,613,576 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000069 ( 0 hom. )

Consequence

FANCC
NM_000136.3 splice_region, intron

Scores

2
Splicing: ADA: 0.9999
2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:3U:6

Conservation

PhyloP100: 5.16
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]
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 5 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
PP5
Variant 9-95135341-C-T is Pathogenic according to our data. Variant chr9-95135341-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 216291.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=3, Uncertain_significance=5}.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
FANCCNM_000136.3 linkc.843+5G>A splice_region_variant, intron_variant Intron 8 of 14 ENST00000289081.8 NP_000127.2 Q00597A0A024R9N2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
FANCCENST00000289081.8 linkc.843+5G>A splice_region_variant, intron_variant Intron 8 of 14 1 NM_000136.3 ENSP00000289081.3 Q00597

Frequencies

GnomAD3 genomes
AF:
0.0000657
AC:
10
AN:
152134
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000103
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000278
AC:
7
AN:
251412
Hom.:
0
AF XY:
0.0000221
AC XY:
3
AN XY:
135900
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:
0.0000327
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000264
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000691
AC:
101
AN:
1461324
Hom.:
0
Cov.:
31
AF XY:
0.0000743
AC XY:
54
AN XY:
726984
show subpopulations
Gnomad4 AFR exome
AF:
0.0000896
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.0000116
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000837
Gnomad4 OTH exome
AF:
0.0000662
GnomAD4 genome
AF:
0.0000657
AC:
10
AN:
152252
Hom.:
0
Cov.:
33
AF XY:
0.0000672
AC XY:
5
AN XY:
74442
show subpopulations
Gnomad4 AFR
AF:
0.0000241
Gnomad4 AMR
AF:
0.0000654
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.000208
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.000103
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000581
Hom.:
0
Bravo
AF:
0.0000491
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:3Uncertain:6
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Fanconi anemia complementation group C Pathogenic:1Uncertain:2
Mar 16, 2017
Counsyl
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Apr 02, 2024
Fulgent Genetics, Fulgent Genetics
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Jul 02, 2018
Mendelics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

not provided Pathogenic:1Uncertain:1
Apr 01, 2024
GeneDx
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Intronic variant directly or indirectly altering the +5 splice site in a gene for which loss of function is a known mechanism of disease, and splice predictors support a deleterious effect; Observed in a patient with breast cancer in published literature (PMID: 35264596); Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 35264596) -

Sep 30, 2022
Quest Diagnostics Nichols Institute San Juan Capistrano
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

To the best of our knowledge, the variant has not been reported in the published literature. The frequency of this variant in the general population, 0.000039 (5/129150 chromosomes, http://gnomad.broadinstitute.org), is uninformative in assessment of its pathogenicity. Analysis of this variant using software algorithms for the prediction of the effect of nucleotide changes on splicing yielded predictions that this variant may affect proper FANCC mRNA splicing . Based on the available information, we are unable to determine the clinical significance of this variant. -

Hereditary cancer-predisposing syndrome Pathogenic:1
Aug 22, 2024
Ambry Genetics
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The c.843+5G>A intronic variant results from a G to A substitution 5 nucleotides after coding exon 7 in the FANCC gene. This alteration was detected in a cohort of 1663 Brazilian breast cancer patients who underwent hereditary multigene panel testing (Guindalini RSC et al. Sci Rep, 2022 Mar;12:4190). 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. RNA studies have demonstrated this alteration results in abnormal splicing in the set of samples tested (Ambry internal data). Based on the majority of available evidence to date, this variant is likely to be pathogenic. -

not specified Uncertain:1
Dec 25, 2022
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant summary: FANCC c.843+5G>A alters a conserved nucleotide located close to a canonical splice site and therefore could affect mRNA splicing, leading to a significantly altered protein sequence. Several computational tools predict a significant impact on normal splicing: Two predict the variant abolishes the canonical 5' splicing donor site. Two predict the variant weakens the canonical 5' splicing donor site. However, these predictions have yet to be confirmed by functional studies. The variant allele was found at a frequency of 2.8e-05 in 251412 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.843+5G>A in individuals affected with Fanconi Anemia Group C and no experimental evidence demonstrating its impact on protein function have been reported. Five clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation (LP, n=2; VUS, n=3). Multiple laboratories reported the variant with conflicting assessments. Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -

Fanconi anemia Uncertain:1
Oct 29, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change falls in intron 8 of the FANCC gene. It does not directly change the encoded amino acid sequence of the FANCC protein. It affects a nucleotide within the consensus splice site. This variant is present in population databases (rs369082921, gnomAD 0.008%). 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: 216291). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). 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 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. -

FANCC-related disorder Uncertain:1
Jul 01, 2024
PreventionGenetics, part of Exact Sciences
Significance: Uncertain significance
Review Status: no assertion criteria provided
Collection Method: clinical testing

The FANCC c.843+5G>A variant is predicted to interfere with splicing. To our knowledge, this variant has not been reported in the literature. This variant is reported in 0.0080% of alleles in individuals of African descent in gnomAD. At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.17
CADD
Uncertain
24
DANN
Benign
0.97
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
1.0
dbscSNV1_RF
Pathogenic
0.99
SpliceAI score (max)
0.86
Details are displayed if max score is > 0.2
DS_DL_spliceai
0.86
Position offset: 5

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.

Other links and lift over

dbSNP: rs369082921; hg19: chr9-97897623; API