17-43057051-C-T

Variant names:

• chr17-43057051-C-T
• rs80358150
• NM_007294.4:c.5277+1G>A

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+1G>A variant causes a splice donor, intron change. The variant allele was found at a frequency of 0.00000137 in 1,461,684 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: "SCV004834029: "A functional study has reported that this variant impacts BRCA1 function in a haploid cell proliferation assay (PMID:30209399)."" and additional evidence is available in ClinVar. The gene BRCA1 is included in the ClinGen Criteria Specification Registry.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: BRCA1 NM_007294.4 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic reviewed by expert panel P:31
• Conservation: PhyloP100: 4.68
• Publications: 23 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 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: SCV004834029: "A functional study has reported that this variant impacts BRCA1 function in a haploid cell proliferation assay (PMID: 30209399)."; SCV005042909: Functional studies indicate that this variant leads to skipping of exon 20 and creates a premature stop codon, proving a damaging effect Tesoriero AA, et al., 2005.; SCV005911619: RT-PCR and sequencing analyses revealed that an 87-bp intron insertion between exon 20 and exon 21 and exon 20 skipping were identified, leading to either a truncated BRCA1 protein or an in-frame deletion of 28 amino acids in the BRCT domain (Ryu et al., 2020; PMID: 32761968).; SCV000076909: Studies have shown that disruption of this splice site results in activation of a cryptic splice site in intron 19 or skipping of exon 19 (also known as exon 20) , and produces a non-functional protein and/or introduces a premature termination codon (PMID: 24667779; internal data).; SCV000699231: The variant was confirmed by experimental evidence showing the variant to result in the skipping of exon 20 and generating a truncated protein (Tesoriero_2005).; SCV000186920: One 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).; SCV000292160: "A functional study has reported that this variant impacts BRCA1 function in a haploid cell proliferation assay (PMID: 30209399)."; SCV005901955: Reported by one calibrated study incorporating mRNA splicing effects to affect protein function similar to pathogenic control variants (PMID:30209399) (PS3).; SCV000108686: Published functional studies demonstrate a damaging effect: classified as non-functional based on a saturation genome editing (SGE) assay measuring cell growth (Findlay 2018); SCV000296332: Functional evidence suggests that this variant may impact protein function and interfere with normal BRCA1 mRNA splicing (PMIDs: 38398132 (2024), 31843900 (2019), 24667779 (2014), 20215541 (2010), 16211554 (2005)).; SCV000591605: Tesoriero et al. (2005) carried out functional studies and determined that this variant leads to two alternative products, one causing exon 20 skipping and leading to a premature stop codon at codon 1737 and the other having retention of exon 20 and leading to a stop codon at codon 1767. PMID:24896178
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 17-43057051-C-T is Pathogenic according to our data. Variant chr17-43057051-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 37654.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.5277+1G>A		splice_donor intron	N/A	NP_009225.1	P38398-1
	BRCA1	NM_001407581.1		c.5343+1G>A		splice_donor intron	N/A	NP_001394510.1	A0A2R8Y7V5
	BRCA1	NM_001407582.1		c.5343+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.5277+1G>A		splice_donor intron	N/A	ENSP00000350283.3	P38398-1
	BRCA1	ENST00000471181.7	TSL:1	c.5340+1G>A		splice_donor intron	N/A	ENSP00000418960.2	P38398-7
	BRCA1	ENST00000470026.6	TSL:1	c.5277+1G>A		splice_donor intron	N/A	ENSP00000419274.2	P38398-1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461684 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727156

African (AFR) AF: 0.00 AC: 0 AN: 33476

American (AMR) AF: 0.00 AC: 0 AN: 44718

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 39696

South Asian (SAS) AF: 0.00 AC: 0 AN: 86254

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53400

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5764

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111860

Other (OTH) AF: 0.00 AC: 0 AN: 60386

GnomAD4 genome Cov.: 31

Alfa AF: 0.00 Hom.: 0

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: reviewed by expert panel

Pathogenic	VUS	Benign	Condition
12	-	-	Breast-ovarian cancer, familial, susceptibility to, 1 (12)
5	-	-	not provided (5)
4	-	-	Hereditary breast ovarian cancer syndrome (4)
4	-	-	Hereditary cancer-predisposing syndrome (4)
1	-	-	Breast and/or ovarian cancer (1)
1	-	-	Breast-ovarian cancer, familial, susceptibility to, 1;C3280442:Pancreatic cancer, susceptibility to, 4;C4554406:Fanconi anemia, complementation group S (1)
1	-	-	Familial cancer of breast;C2676676:Breast-ovarian cancer, familial, susceptibility to, 1;C4554406:Fanconi anemia, complementation group S (1)
1	-	-	Hereditary breast ovarian cancer syndrome;C2676676:Breast-ovarian cancer, familial, susceptibility to, 1 (1)
1	-	-	Malignant tumor of breast (1)
1	-	-	not specified (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.38	D
BayesDel_noAF	Pathogenic	0.30
CADD	Pathogenic	29
DANN	Uncertain	0.99
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.86
FATHMM_MKL	Pathogenic	0.97	D
PhyloP100		4.7
GERP RS		5.1
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.8
Mutation Taster		=0/100	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
Splicevardb		3.0
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: rs80358150; hg19: chr17-41209068; COSMIC: COSV58785677;