rs1555561294

Positions:

• chr16-89791402-C-G

Variant summary

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

The NM_000135.4(FANCA):​c.1359+1G>C variant causes a splice donor change. The variant allele was found at a frequency of 0.00000137 in 1,461,514 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: 0.0000014 (0 hom.)
• Consequence: FANCA NM_000135.4 splice_donor
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 6.13

Genes affected

FANCA (HGNC:3582): (FA complementation group A) 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 A. Alternative splicing results in multiple transcript variants encoding different isoforms. Mutations in this gene are the most common cause of Fanconi anemia. [provided by RefSeq, Jul 2008]

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, No cryptic splice site detected. Exon removal results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 16-89791402-C-G is Pathogenic according to our data. Variant chr16-89791402-C-G is described in ClinVar as [Pathogenic]. Clinvar id is 556465.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr16-89791402-C-G is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
FANCA	NM_000135.4	c.1359+1G>C		splice_donor_variant		ENST00000389301.8	NP_000126.2
FANCA	NM_001286167.3	c.1359+1G>C		splice_donor_variant			NP_001273096.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
FANCA	ENST00000389301.8	c.1359+1G>C		splice_donor_variant		1	NM_000135.4	ENSP00000373952	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461514 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727050

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: 0.00000180

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Fanconi anemia complementation group A Pathogenic:3

Pathogenic, no assertion criteria provided	curation	Leiden Open Variation Database	Feb 28, 2020	Curator: Arleen D. Auerbach. Submitter to LOVD: Arleen D. Auerbach. -
Pathogenic, criteria provided, single submitter	clinical testing	Counsyl	Jan 31, 2018	- -
Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Jan 11, 2022	- -

Fanconi anemia Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 17, 2022

For these reasons, this variant has been classified as Pathogenic. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. ClinVar contains an entry for this variant (Variation ID: 556465). This variant is also known as IVS14 + 1G>C. Disruption of this splice site has been observed in individuals with Fanconi anemia (PMID: 9399890, 24584348). This variant is not present in population databases (gnomAD no frequency). This sequence change affects a donor splice site in intron 14 of the FANCA 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 FANCA are known to be pathogenic (PMID: 19367192). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.44	D
BayesDel_noAF	Pathogenic	0.40
CADD	Pathogenic	32
DANN	Uncertain	1.0
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.96
FATHMM_MKL	Pathogenic	0.98	D
MutationTaster	Benign	1.0	D;D
GERP RS		5.4
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.7

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_DL_spliceai		1.0		Position offset: 1

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

Publications

LitVar

Other links and lift over

dbSNP: rs1555561294; hg19: chr16-89857810;