17-43051098-A-G

Variant names:

• chr17-43051098-A-G
• rs80357463
• NM_007294.4:c.5297T>C

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PM1 PM2 PM5 PP3_Moderate PP5_Moderate

The NM_007294.4(BRCA1):​c.5297T>C​(p.Ile1766Thr) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. I1766M) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 31)
• Consequence: BRCA1 NM_007294.4 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 5.03
• Publications: 31 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):

• breast-ovarian cancer, familial, susceptibility to, 1

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

  Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE, LIMITED Submitted by: G2P, Labcorp Genetics (formerly Invitae), ClinGen, 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 10 ACMG points.

• PM1: In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 14 benign, 84 uncertain in NM_007294.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr17-43051098-A-C is described in ClinVar as Pathogenic. ClinVar VariationId is 37656.Status of the report is reviewed_by_expert_panel, 3 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.902
• PP5: Variant 17-43051098-A-G is Pathogenic according to our data. Variant chr17-43051098-A-G is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 867965.Status of the report is criteria_provided_single_submitter, 1 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

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	BRCA1	NM_007294.4	MANE Select	c.5297T>C	p.Ile1766Thr	missense	Exon 20 of 23	NP_009225.1
	BRCA1	NM_001407581.1		c.5363T>C	p.Ile1788Thr	missense	Exon 21 of 24	NP_001394510.1
	BRCA1	NM_001407582.1		c.5363T>C	p.Ile1788Thr	missense	Exon 21 of 24	NP_001394511.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	BRCA1	ENST00000357654.9	TSL:1 MANE Select	c.5297T>C	p.Ile1766Thr	missense	Exon 20 of 23	ENSP00000350283.3
	BRCA1	ENST00000471181.7	TSL:1	c.5360T>C	p.Ile1787Thr	missense	Exon 21 of 24	ENSP00000418960.2
	BRCA1	ENST00000470026.6	TSL:1	c.5297T>C	p.Ile1766Thr	missense	Exon 20 of 23	ENSP00000419274.2

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 31

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hereditary breast ovarian cancer syndrome Pathogenic:1

Jul 24, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with ovarian cancer (PMID: 28692638). ClinVar contains an entry for this variant (Variation ID: 867965). Advanced modeling performed at Invitae incorporating data from internal and/or published experimental studies (PMID: 30209399) indicates that this missense variant is expected to disrupt BRCA1 function. Experimental studies have shown that this missense change affects BRCA1 function (PMID: 30209399). This variant disrupts the p.Ile1766 amino acid residue in BRCA1. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 14534301, 16528612, 17305420, 17308087, 18680205, 19493677, 20516115, 30765603). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. This sequence change replaces isoleucine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 1766 of the BRCA1 protein (p.Ile1766Thr).

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.89
BayesDel_addAF	Pathogenic	0.34	D
BayesDel_noAF	Pathogenic	0.25
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Benign	0.17	T
Eigen	Uncertain	0.65
Eigen_PC	Uncertain	0.62
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Uncertain	0.93	D
M_CAP	Pathogenic	0.66	D
MetaRNN	Pathogenic	0.90	D
MetaSVM	Pathogenic	0.82	D
MutationAssessor	Uncertain	2.1	M
PhyloP100		5.0
PrimateAI	Uncertain	0.51	T
PROVEAN	Uncertain	-4.0	D
REVEL	Pathogenic	0.73
Sift	Uncertain	0.0020	D
Sift4G	Uncertain	0.0020	D
Polyphen		0.91	P
Vest4		0.84
MVP		1.0
MPC		0.50
ClinPred		0.96	D
GERP RS		5.1
RBP_binding_hub_radar		0.92
RBP_regulation_power_radar		2.0
Varity_R		0.60
gMVP		0.77

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs80357463; hg19: chr17-41203115;