chr17-43082403-C-T

Variant names:

• chr17-43082403-C-T
• rs80358027
• NM_007294.4:c.4357+1G>A

Variant summary

Our verdict is Pathogenic. The variant received 22 ACMG points: 22P and 0B. PVS1 PS3 PM2 PP5_Very_Strong

The NM_007294.4(BRCA1):​c.4357+1G>A variant causes a splice donor, intron change. The variant allele was found at a frequency of 0.00000186 in 1,613,594 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 (★★★). ClinVar reports functional evidence for this variant: "SCV000839903: In silico analysis and experimental studies suggest that this variant causes exon 13 skipping (PMID24667779,21735045, 21769658)." and additional evidence is available in ClinVar. The gene BRCA1 is included in the ClinGen Criteria Specification Registry.

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: BRCA1 NM_007294.4 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic reviewed by expert panel P:24
• Conservation: PhyloP100: 3.70
• Publications: 42 publications found

Genes affected

BRCA1 (HGNC:1100): (BRCA1 DNA repair associated) This gene encodes a 190 kD nuclear phosphoprotein that plays a role in maintaining genomic stability, and it also acts as a tumor suppressor. The BRCA1 gene contains 22 exons spanning about 110 kb of DNA. The encoded protein combines with other tumor suppressors, DNA damage sensors, and signal transducers to form a large multi-subunit protein complex known as the BRCA1-associated genome surveillance complex (BASC). This gene product associates with RNA polymerase II, and through the C-terminal domain, also interacts with histone deacetylase complexes. This protein thus plays a role in transcription, DNA repair of double-stranded breaks, and recombination. Mutations in this gene are responsible for approximately 40% of inherited breast cancers and more than 80% of inherited breast and ovarian cancers. Alternative splicing plays a role in modulating the subcellular localization and physiological function of this gene. Many alternatively spliced transcript variants, some of which are disease-associated mutations, have been described for this gene, but the full-length natures of only some of these variants has been described. A related pseudogene, which is also located on chromosome 17, has been identified. [provided by RefSeq, May 2020]

BRCA1 Gene-Disease associations (from GenCC):

• BRCA1-related cancer predisposition

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• breast-ovarian cancer, familial, susceptibility to, 1

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Ambry Genetics
• Fanconi anemia, complementation group S

  Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE, LIMITED Submitted by: G2P, ClinGen, Labcorp Genetics (formerly Invitae), Ambry Genetics
• pancreatic cancer, susceptibility to, 4

  Inheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
• hereditary breast ovarian cancer syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Fanconi anemia

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Specifications for BRCA1 are available in the ClinGen Criteria Specification Registry and recommended for reference when assigning criteria.

Our verdict: Pathogenic. The variant received 22 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.
• PS3: PS3 evidence extracted from ClinVar submissions: SCV000839903: In silico analysis and experimental studies suggest that this variant causes exon 13 skipping (PMID24667779,21735045, 21769658).; SCV004101329: A functional study conducted in patient cells demonstrated that this variant results in abnormal splicing which is predicted to result in a frameshift and premature termination of translation, leading to nonsense mediated mRNA decay (PMID: 21769658).; SCV002047917: RNA analyses from a patient carrying this variant demonstrate skipping of exon 13, leading to a frameshift (Thomassen 2012). PMID: 21769658; SCV000186934: Functional analyses have demonstrated that this alteration leads to a skipping of coding exon 11 (also known as exon 13), causing a frameshift and alternate stop codon (Ambry internal data; Thomassen M et al. Breast Cancer Res. Treat. 2012 Apr;132:1009-23).; SCV000688488: RNA studies have reported this variant to cause the out-of-frame skipping of exon 12 in carrier RNA and in minigene splicing assay (PMID: 21769658, 24667779 ).; SCV000076545: Studies have shown that disruption of this splice site alters mRNA splicing and is expected to lead to the loss of protein expression (PMID: 21735045, 21769658, 24667779; internal data).; SCV000699137: RT-PCR showing that it leads to skipping of exon 12 (legacy exon 13) and frameshift p.Arg1397TyrfsX2 (Thomassen_2011).; SCV004848440: Experimental studies have shown that this variant causes exon 12 skipping in BRCA1 (Steffensen 2014 PMID: 24667779, Thomassen 2012 PMID: 21769658).; SCV005427183: In silico analysis and experimental studies suggest that this variant causes exon 13 skipping (PMID24667779,21735045, 21769658).
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 17-43082403-C-T is Pathogenic according to our data. Variant chr17-43082403-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 37584.Status of the report is reviewed_by_expert_panel, 3 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_007294.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	BRCA1	NM_007294.4	MANE Select	c.4357+1G>A		splice_donor intron	N/A	NP_009225.1	P38398-1
	BRCA1	NM_001407581.1		c.4357+1G>A		splice_donor intron	N/A	NP_001394510.1	A0A2R8Y7V5
	BRCA1	NM_001407582.1		c.4357+1G>A		splice_donor intron	N/A	NP_001394511.1	A0A2R8Y7V5

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	BRCA1	ENST00000357654.9	TSL:1 MANE Select	c.4357+1G>A		splice_donor intron	N/A	ENSP00000350283.3	P38398-1
	BRCA1	ENST00000471181.7	TSL:1	c.4357+1G>A		splice_donor intron	N/A	ENSP00000418960.2	P38398-7
	BRCA1	ENST00000470026.6	TSL:1	c.4357+1G>A		splice_donor intron	N/A	ENSP00000419274.2	P38398-1

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152156 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000241

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: 0.0000942

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251154 AF XY: 0.00

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.0000463

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461320 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 726870

African (AFR) AF: 0.0000299 AC: 1 AN: 33466

American (AMR) AF: 0.00 AC: 0 AN: 44688

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26118

East Asian (EAS) AF: 0.00 AC: 0 AN: 39680

South Asian (SAS) AF: 0.00 AC: 0 AN: 86228

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53412

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111582

Other (OTH) AF: 0.00 AC: 0 AN: 60378

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152274 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74460

African (AFR) AF: 0.0000241 AC: 1 AN: 41560

American (AMR) AF: 0.00 AC: 0 AN: 15290

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5180

South Asian (SAS) AF: 0.00 AC: 0 AN: 4814

European-Finnish (FIN) AF: 0.0000942 AC: 1 AN: 10618

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68022

Other (OTH) AF: 0.00 AC: 0 AN: 2114

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.0000113

ExAC AF: 0.00000824 AC: 1

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: reviewed by expert panel

Pathogenic	VUS	Benign	Condition
11	-	-	Breast-ovarian cancer, familial, susceptibility to, 1 (11)
5	-	-	not provided (5)
4	-	-	Hereditary breast ovarian cancer syndrome (4)
3	-	-	Hereditary cancer-predisposing syndrome (3)
1	-	-	BRCA1-related cancer predisposition (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.41	D
BayesDel_noAF	Pathogenic	0.36
CADD	Pathogenic	28
DANN	Uncertain	0.99
Eigen	Pathogenic	0.99
Eigen_PC	Pathogenic	0.82
FATHMM_MKL	Uncertain	0.95	D
PhyloP100		3.7
GERP RS		5.3
Mutation Taster		=0/100	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
SpliceAI score (max)		0.99		Details are displayed if max score is > 0.2
DS_DL_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: rs80358027; hg19: chr17-41234420;