rs769547477

Positions:

• chr9-35076030-T-C

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_004629.2(FANCG):​c.1077-2A>G variant causes a splice acceptor, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000684 in 1,461,652 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 Pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000068 (0 hom.)
• Consequence: FANCG NM_004629.2 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:10
• Conservation: PhyloP100: 3.38

Genes affected

FANCG (HGNC:3588): (FA complementation group G) 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 G. [provided by RefSeq, Jul 2008]

FANCG (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, Cryptic splice site detected, with MaxEntScore 5.8, offset of 5, new splice context is: gcttttactcctcggggcAGgag. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 9-35076030-T-C is Pathogenic according to our data. Variant chr9-35076030-T-C is described in ClinVar as [Pathogenic]. Clinvar id is 445394.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr9-35076030-T-C is described in Lovd as [Pathogenic]. Variant chr9-35076030-T-C is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
FANCG	NM_004629.2	c.1077-2A>G		splice_acceptor_variant, intron_variant		ENST00000378643.8	NP_004620.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
FANCG	ENST00000378643.8	c.1077-2A>G		splice_acceptor_variant, intron_variant		1	NM_004629.2	ENSP00000367910.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.0000160 AC: 4 AN: 250236 Hom.: 0 AF XY: 0.0000222 AC XY: 3 AN XY: 135398

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000868

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: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000684 AC: 10 AN: 1461652 Hom.: 0 Cov.: 32 AF XY: 0.00000550 AC XY: 4 AN XY: 727104

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000671

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: 0.00000450

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 32

Bravo AF: 0.0000151

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:10

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Fanconi anemia complementation group G Pathogenic:6

Pathogenic, criteria provided, single submitter	clinical testing	Molecular Diagnostics Laboratory, M Health Fairview: University of Minnesota	Mar 31, 2017	- -
Pathogenic, criteria provided, single submitter	clinical testing	Laboratorio de Genetica e Diagnostico Molecular, Hospital Israelita Albert Einstein	Nov 27, 2021	ACMG classification criteria: PVS1 very strong, PS3 supporting, PS4 moderate, PM2 moderate, PM3 moderate, PP1 supporting -
Pathogenic, no assertion criteria provided	curation	Leiden Open Variation Database	Feb 28, 2020	Curator: Arleen D. Auerbach. Submitters to LOVD: Arleen D. Auerbach, Avani P. Solanki, Daniela Pilonetto, Johan de Winter. -
Pathogenic, no assertion criteria provided	clinical testing	Natera, Inc.	Sep 16, 2020	- -
Pathogenic, criteria provided, single submitter	clinical testing	Fulgent Genetics, Fulgent Genetics	May 26, 2022	- -
Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Jan 21, 2024	- -

not provided Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Mar 26, 2022	Published functional studies demonstrate a damaging effect (exon skipping or usage of a cryptic splice donor site leading to multiple aberrant transcripts) (Auerbach et al., 2003); This variant is associated with the following publications: (PMID: 25525159, 11438206, 33718801, 11093276, 12552564) -
Pathogenic, criteria provided, single submitter	clinical testing	Center for Pediatric Genomic Medicine, Children's Mercy Hospital and Clinics	May 31, 2017	- -
Pathogenic, criteria provided, single submitter	clinical testing	Greenwood Genetic Center Diagnostic Laboratories, Greenwood Genetic Center	Feb 09, 2021	PVS1, PS3, PM2 -

Fanconi anemia Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 22, 2023

This sequence change affects an acceptor splice site in intron 8 of the FANCG gene. RNA analysis indicates that disruption of this splice site induces altered splicing and may result in an absent or disrupted protein product. This variant is present in population databases (rs769547477, gnomAD 0.009%). Disruption of this splice site has been observed in individuals with Fanconi anaemia (PMID: 11093276, 12552564, 28717661). This variant is also known as IVS8-2A>G. ClinVar contains an entry for this variant (Variation ID: 445394). Studies have shown that disruption of this splice site results in skipping of exon 9 and activation of a cryptic splice site and introduces a premature termination codon (PMID: 11093276). The resulting mRNA is expected to undergo nonsense-mediated decay. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.48	D
BayesDel_noAF	Uncertain	0.12
CADD	Pathogenic	26
DANN	Uncertain	0.99
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.83
FATHMM_MKL	Uncertain	0.97	D
GERP RS		5.3
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	0.93
SpliceAI score (max)		0.79		Details are displayed if max score is > 0.2
DS_AL_spliceai		0.79		Position offset: -2

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

Publications

LitVar

Other links and lift over

dbSNP: rs769547477; hg19: chr9-35076027;