NM_007294.4:c.5277+1delG

Variant names:

• chr17-43057050-AC-A
• rs273901754
• NM_007294.4:c.5277+1delG

Variant summary

Our verdict is Pathogenic. The variant received 16 ACMG points: 16P and 0B. PVS1_Moderate PS3 PM2 PP5_Very_Strong

The NM_007294.4(BRCA1):​c.5277+1delG variant causes a splice donor, intron change. The variant was absent in control chromosomes in GnomAD project. 1/1 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★). ClinVar reports functional evidence for this variant: "SCV001733556: canonical splice site variants at this donor site, c.5277+1G>A and c.5277+1G>T, have been reported as disease-causing in ClinVar due to evidence of RNA splicing defect, reports in multiple individuals and families affected with breast and ovarian cancer and loss-of-function in experimental functional study (ClinVar variation ID: 37654, 462668).; SCV000293939: Disrupts the critical BRCT 2 domain (UniProt); Also known as 5396+1delG; IVS20+1delG; This variant is associated with the following publications: (PMID:28152038, 22535016, 30787465, 35875314, 25348405, 29446198, 16267036, 33287145)".

• Frequency: Genomes: not found (cov: 31)
• Consequence: BRCA1 NM_007294.4 splice_donor, intron
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:11
• Conservation: PhyloP100: 4.68
• Publications: 5 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

Our verdict: Pathogenic. The variant received 16 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.015021459 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
• PS3: PS3 evidence extracted from ClinVar submissions: SCV001733556: canonical splice site variants at this donor site, c.5277+1G>A and c.5277+1G>T, have been reported as disease-causing in ClinVar due to evidence of RNA splicing defect, reports in multiple individuals and families affected with breast and ovarian cancer and loss-of-function in experimental functional study (ClinVar variation ID: 37654, 462668).; SCV000293939: Disrupts the critical BRCT 2 domain (UniProt); Also known as 5396+1delG; IVS20+1delG; This variant is associated with the following publications: (PMID: 28152038, 22535016, 30787465, 35875314, 25348405, 29446198, 16267036, 33287145)
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 17-43057050-AC-A is Pathogenic according to our data. Variant chr17-43057050-AC-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 91644.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.5277+1delG		splice_donor intron	N/A	NP_009225.1	P38398-1
	BRCA1	NM_001407581.1		c.5343+1delG		splice_donor intron	N/A	NP_001394510.1	A0A2R8Y7V5
	BRCA1	NM_001407582.1		c.5343+1delG		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.5277+1delG		splice_donor intron	N/A	ENSP00000350283.3	P38398-1
	BRCA1	ENST00000471181.7	TSL:1	c.5340+1delG		splice_donor intron	N/A	ENSP00000418960.2	P38398-7
	BRCA1	ENST00000470026.6	TSL:1	c.5277+1delG		splice_donor intron	N/A	ENSP00000419274.2	P38398-1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 31

ClinVar

ClinVar submissions

Significance: Pathogenic/Likely pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
5	-	-	Breast-ovarian cancer, familial, susceptibility to, 1 (5)
2	-	-	Hereditary breast ovarian cancer syndrome (2)
2	-	-	Hereditary cancer-predisposing syndrome (2)
2	-	-	not provided (2)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		4.7
Mutation Taster		=0/100	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.84		Position offset: 3
DS_DL_spliceai		1.0		Position offset: 2

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

Other links and lift over

dbSNP: rs273901754; hg19: chr17-41209067;