17-43063916-A-G

Variant names:

• chr17-43063916-A-G
• rs1555578599
• NM_007294.4:c.5110T>C

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM1 PM2 PM5

The NM_007294.4(BRCA1):​c.5110T>C​(p.Phe1704Leu) variant causes a missense change. The variant allele was found at a frequency of 0.00000137 in 1,461,814 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. F1704C) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: BRCA1 NM_007294.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:4
• Conservation: PhyloP100: 5.76
• Publications: 2 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: Likely_pathogenic. The variant received 6 ACMG points.

• PM1: In a hotspot region, there are 23 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 7 benign, 65 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 chr17-43063915-A-G is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 864965.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BRCA1	NM_007294.4	c.5110T>C	p.Phe1704Leu	missense_variant	Exon 17 of 23	ENST00000357654.9	NP_009225.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BRCA1	ENST00000357654.9	c.5110T>C	p.Phe1704Leu	missense_variant	Exon 17 of 23	1	NM_007294.4	ENSP00000350283.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461814 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727200

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26132

East Asian (EAS) AF: 0.00 AC: 0 AN: 39680

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

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53414

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111970

Other (OTH) AF: 0.00 AC: 0 AN: 60392

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Uncertain:1

Nov 21, 2016

Quest Diagnostics Nichols Institute San Juan Capistrano

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Breast-ovarian cancer, familial, susceptibility to, 1 Uncertain:1

Sep 05, 2023

Baylor Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Hereditary cancer-predisposing syndrome Uncertain:1

May 04, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.F1704L variant (also known as c.5110T>C), located in coding exon 16 of the BRCA1 gene, results from a T to C substitution at nucleotide position 5110. The phenylalanine at codon 1704 is replaced by leucine, an amino acid with highly similar properties. One functional study found that this nucleotide substitution is non-functional in a high-throughput, genome editing, haploid cell survival assay (Findlay GM et al. Nature, 2018 10;562:217-222). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the available evidence, the clinical significance of this variant remains unclear. -

Hereditary breast ovarian cancer syndrome Uncertain:1

Aug 11, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces phenylalanine, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 1704 of the BRCA1 protein (p.Phe1704Leu). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with BRCA1-related conditions. ClinVar contains an entry for this variant (Variation ID: 440479). 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). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.97
BayesDel_addAF	Pathogenic	0.32	D
BayesDel_noAF	Pathogenic	0.23
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Benign	0.15	.;T;.;.;T;T;.;.;.;T;.
Eigen	Uncertain	0.53
Eigen_PC	Uncertain	0.60
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Uncertain	0.97	D;D;D;D;D;D;D;D;D;D;D
M_CAP	Pathogenic	0.45	D
MetaRNN	Uncertain	0.74	D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Uncertain	0.18	D
MutationAssessor	Benign	1.6	.;L;.;.;.;.;.;.;.;.;.
PhyloP100		5.8
PrimateAI	Pathogenic	0.82	D
PROVEAN	Uncertain	-4.2	D;N;.;D;.;.;N;D;D;N;D
REVEL	Uncertain	0.63
Sift	Benign	0.26	T;D;.;T;.;.;D;T;T;T;T
Sift4G	Uncertain	0.011	D;D;D;D;D;D;D;D;.;.;D
Polyphen		0.0040, 1.0	.;B;.;.;.;D;.;.;.;D;.
Vest4		0.77
MVP		0.97
MPC		0.29
ClinPred		0.94	D
GERP RS		5.8
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.8
Varity_R		0.93
gMVP		0.78
Mutation Taster		=4/96	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.080		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: rs1555578599; hg19: chr17-41215933;