17-43074522-C-T

Variant names:

• chr17-43074522-C-T
• rs80358189
• NM_007294.4:c.4485-1G>A

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_007294.4(BRCA1):​c.4485-1G>A variant causes a splice acceptor, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,460,784 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 Pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: BRCA1 NM_007294.4 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:14
• Conservation: PhyloP100: 2.00
• Publications: 19 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 18 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, Cryptic splice site detected, with MaxEntScore 5.7, offset of 1, new splice context is: cttccatttatctttctaAGtca. Cryptic site results in frameshift 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 17-43074522-C-T is Pathogenic according to our data. Variant chr17-43074522-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 55213.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.4485-1G>A		splice_acceptor intron	N/A	NP_009225.1	P38398-1
	BRCA1	NM_001407581.1		c.4551-1G>A		splice_acceptor intron	N/A	NP_001394510.1	A0A2R8Y7V5
	BRCA1	NM_001407582.1		c.4551-1G>A		splice_acceptor 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.4485-1G>A		splice_acceptor intron	N/A	ENSP00000350283.3	P38398-1
	BRCA1	ENST00000471181.7	TSL:1	c.4548-1G>A		splice_acceptor intron	N/A	ENSP00000418960.2	P38398-7
	BRCA1	ENST00000470026.6	TSL:1	c.4485-1G>A		splice_acceptor intron	N/A	ENSP00000419274.2	P38398-1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD2 exomes AF: 0.0000119 AC: 3 AN: 251076 AF XY: 0.0000147

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: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1460784 Hom.: 0 Cov.: 30 AF XY: 0.00000413 AC XY: 3 AN XY: 726756

African (AFR) AF: 0.00 AC: 0 AN: 33448

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

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26128

East Asian (EAS) AF: 0.00 AC: 0 AN: 39686

South Asian (SAS) AF: 0.0000464 AC: 4 AN: 86214

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53396

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5758

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111070

Other (OTH) AF: 0.00 AC: 0 AN: 60362

GnomAD4 genome Cov.: 31

Alfa AF: 0.00 Hom.: 0

ExAC AF: 0.0000165 AC: 2

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
5	-	-	Breast-ovarian cancer, familial, susceptibility to, 1 (5)
3	-	-	Hereditary breast ovarian cancer syndrome (3)
2	-	-	Hereditary cancer-predisposing syndrome (2)
1	-	-	Familial cancer of breast;C2676676:Breast-ovarian cancer, familial, susceptibility to, 1;C3280442:Pancreatic cancer, susceptibility to, 4;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 provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Benign	-0.30	T
BayesDel_noAF	Benign	-0.47
CADD	Pathogenic	33
DANN	Benign	0.92
Eigen	Uncertain	0.62
Eigen_PC	Uncertain	0.34
FATHMM_MKL	Benign	0.68	D
PhyloP100		2.0
GERP RS		4.2
Mutation Taster		=0/100	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.88
SpliceAI score (max)		0.97		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.58		Position offset: -30
DS_AL_spliceai		0.97		Position offset: -1

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

Other links and lift over

dbSNP: rs80358189; hg19: chr17-41226539;