rs1555540076

Variant names:

• chr16-89752223-C-G
• rs1555540076
• NM_000135.4:c.2982-1G>C

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1_Moderate PM2 PP5_Very_Strong

The NM_000135.4(FANCA):​c.2982-1G>C variant causes a splice acceptor, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000685 in 1,460,516 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 Likely pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000068 (0 hom.)
• Consequence: FANCA NM_000135.4 splice_acceptor, intron
• Scores: Splicing: ADA: 0.9999
• Clinical Significance: Likely pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 2.22
• Publications: 0 publications found

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]

FANCA Gene-Disease associations (from GenCC):

• Fanconi anemia complementation group A

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Laboratory for Molecular Medicine, ClinGen, Ambry Genetics, Labcorp Genetics (formerly Invitae), Myriad Women’s Health, G2P
• Fanconi anemia

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 12 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.019459708 fraction of the gene. Cryptic splice site detected, with MaxEntScore 5.5, offset of 6, new splice context is: tattttcatttcacctcaAGgag. Cryptic site results in inframe 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 16-89752223-C-G is Pathogenic according to our data. Variant chr16-89752223-C-G is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 554136.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000135.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	FANCA	NM_000135.4	MANE Select	c.2982-1G>C		splice_acceptor intron	N/A	NP_000126.2
	FANCA	NM_001286167.3		c.2982-1G>C		splice_acceptor intron	N/A	NP_001273096.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	FANCA	ENST00000389301.8	TSL:1 MANE Select	c.2982-1G>C		splice_acceptor intron	N/A	ENSP00000373952.3
	FANCA	ENST00000564475.6	TSL:2	c.2982-1G>C		splice_acceptor intron	N/A	ENSP00000454977.2
	FANCA	ENST00000568369.6	TSL:2	c.2982-1G>C		splice_acceptor intron	N/A	ENSP00000456829.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000685 AC: 10 AN: 1460516 Hom.: 0 Cov.: 31 AF XY: 0.00000688 AC XY: 5 AN XY: 726672

African (AFR) AF: 0.00 AC: 0 AN: 33444

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26130

East Asian (EAS) AF: 0.00 AC: 0 AN: 39694

South Asian (SAS) AF: 0.00 AC: 0 AN: 86238

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53236

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.00000900 AC: 10 AN: 1110944

Other (OTH) AF: 0.00 AC: 0 AN: 60342

GnomAD4 genome Cov.: 32

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

ClinVar submissions as Germline

Significance: Likely pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
3	-	-	Fanconi anemia complementation group A (3)
1	-	-	Fanconi anemia (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Benign	-0.12	T
BayesDel_noAF	Benign	-0.41
CADD	Uncertain	25
DANN	Benign	0.96
Eigen	Uncertain	0.61
Eigen_PC	Uncertain	0.33
FATHMM_MKL	Uncertain	0.89	D
PhyloP100		2.2
GERP RS		3.7
Mutation Taster		=10/90	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.90
SpliceAI score (max)		0.99		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.52		Position offset: -7
DS_AL_spliceai		0.99		Position offset: -1

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

Other links and lift over

dbSNP: rs1555540076; hg19: chr16-89818631;