17-43049117-T-C

Variant names:

• chr17-43049117-T-C
• rs397509279
• NM_007294.4:c.5406+4A>G

Variant summary

Our verdict is Pathogenic. The variant received 15 ACMG points: 15P and 0B. PS3 PM2 PP3 PP5_Very_Strong

The NM_007294.4(BRCA1):​c.5406+4A>G variant causes a splice region, intron change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★). ClinVar reports functional evidence for this variant: "SCV000322145: Published functional studies demonstrate a damaging effect: classified as non-functional based on a saturation genome editing (SGE) assay measuring cell growth (Findlay 2018)" and additional evidence is available in ClinVar. The gene BRCA1 is included in the ClinGen Criteria Specification Registry.

• Frequency: Genomes: not found (cov: 31)
• Consequence: BRCA1 NM_007294.4 splice_region, intron
• Scores: Splicing: ADA: 0.9996
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:7
• Conservation: PhyloP100: 4.37
• Publications: 3 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, Labcorp Genetics (formerly Invitae), Ambry Genetics, ClinGen
• 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 15 ACMG points.

• PS3: PS3 evidence extracted from ClinVar submissions: SCV000322145: Published functional studies demonstrate a damaging effect: classified as non-functional based on a saturation genome editing (SGE) assay measuring cell growth (Findlay 2018); SCV001186002: A similar alteration, BRCA1 c.5406+5C>G was shown to have the same splice defect (Houdayer C et al. Hum. Mutat., 2012 Aug;33:1228-38). Another functional study found that this nucleotide substitution is deleterious in a high-throughput, genome editing, haploid cell survival assay (Findlay GM et al. Nature, 2018 10;562:217-222).; SCV001357539: Functional RNA studies have shown that this variant causes skipping of exon 22, resulting in premature truncation of the BRCA1 protein (PMID 27616075, 23239986).; SCV003927202: multiple studies with patient-derived RNA showed that the cDNA had skipping of coding exon 20 (also known as Exon 22) leading to a frameshift with predicted premature termination codon (Wappenschmidt B et al. PLoS ONE, 2012 Dec;7:e50800; Kraus C et al. Int. J. Cancer, 2017 Jan;140:95-102).; SCV003441929: Experimental studies have shown that this variant affects BRCA1 function (PMID: 30209399).
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. No scorers claiming Uncertain. Scorers claiming Benign: max_spliceai.
• PP5: Variant 17-43049117-T-C is Pathogenic according to our data. Variant chr17-43049117-T-C is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 55563.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 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.5406+4A>G		splice_region intron	N/A	NP_009225.1	P38398-1
	BRCA1	NM_001407581.1		c.5472+4A>G		splice_region intron	N/A	NP_001394510.1	A0A2R8Y7V5
	BRCA1	NM_001407582.1		c.5472+4A>G		splice_region 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.5406+4A>G		splice_region intron	N/A	ENSP00000350283.3	P38398-1
	BRCA1	ENST00000471181.7	TSL:1	c.5469+4A>G		splice_region intron	N/A	ENSP00000418960.2	P38398-7
	BRCA1	ENST00000470026.6	TSL:1	c.5406+4A>G		splice_region intron	N/A	ENSP00000419274.2	P38398-1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 31

Alfa AF: 0.0000293 Hom.: 0

ClinVar

ClinVar submissions

Significance: Pathogenic/Likely pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
3	-	-	not provided (3)
2	-	-	Hereditary cancer-predisposing syndrome (2)
1	-	-	Breast-ovarian cancer, familial, susceptibility to, 1 (1)
1	-	-	Hereditary breast ovarian cancer syndrome (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.30
CADD	Benign	23
DANN	Benign	0.96
PhyloP100		4.4
Mutation Taster		=0/100	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.98
Splicevardb		3.0
SpliceAI score (max)		0.12		Details are displayed if max score is > 0.2

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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

dbSNP: rs397509279;

hg19: chr17-41201134;