17-43049193-A-T

Position:

• chr17-43049193-A-T

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PVS1 PM2

The ENST00000591849.5(BRCA1):​c.33T>A​(p.Tyr11*) variant causes a stop gained, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,692 control chromosomes in the GnomAD database, with no homozygous occurrence. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. Y11Y) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: BRCA1 ENST00000591849.5 stop_gained, splice_region
• Scores: Splicing: ADA: 0.1253
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:4 O:1
• Conservation: PhyloP100: 1.17

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]

ACMG classification

Verdict is Pathogenic. Variant got 10 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant located near the start codon (<100nt), not predicted to undergo nonsense mediated mRNA decay. There are 217 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BRCA1	NM_007294.4	c.5334T>A	p.Asp1778Glu	missense_variant, splice_region_variant	21/23	ENST00000357654.9	NP_009225.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BRCA1	ENST00000357654.9	c.5334T>A	p.Asp1778Glu	missense_variant, splice_region_variant	21/23	1	NM_007294.4	ENSP00000350283.3

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461692 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727162

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 31

Asia WGS AF: 0.000289 AC: 1 AN: 3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary breast ovarian cancer syndrome Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Sep 01, 2022	This sequence change replaces aspartic acid, which is acidic and polar, with glutamic acid, which is acidic and polar, at codon 1778 of the BRCA1 protein (p.Asp1778Glu). 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. Experimental studies have shown that this missense change does not substantially affect BRCA1 function (PMID: 32803532). Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated. ClinVar contains an entry for this variant (Variation ID: 865356). This variant has not been reported in the literature in individuals affected with BRCA1-related conditions. This variant is not present in population databases (gnomAD no frequency). -
Uncertain significance, criteria provided, single submitter	clinical testing	Breast Center, Key Laboratory of Carcinogenesis and Translational Research	May 01, 2020	- -

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

not provided, no classification provided	in vitro	Brotman Baty Institute, University of Washington	-	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Baylor Genetics	Mar 17, 2024	- -

Breast and/or ovarian cancer Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario

Feb 23, 2023

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.17
BayesDel_addAF	Pathogenic	0.18	D
BayesDel_noAF	Uncertain	0.020
CADD	Benign	18
DANN	Uncertain	0.99
DEOGEN2	Benign	0.12	.;T;.;T;T;.;.
Eigen	Benign	0.15
Eigen_PC	Benign	0.20
FATHMM_MKL	Uncertain	0.86	D
LIST_S2	Benign	0.81	T;T;T;T;T;T;T
MetaRNN	Uncertain	0.47	T;T;T;T;T;T;T
MetaSVM	Uncertain	0.036	D
MutationAssessor	Benign	1.8	.;L;.;.;.;.;.
PrimateAI	Benign	0.40	T
PROVEAN	Uncertain	-2.6	D;N;.;.;.;N;N
REVEL	Uncertain	0.53
Sift	Benign	0.24	T;D;.;.;.;D;T
Sift4G	Benign	0.41	T;T;T;T;T;T;T
Polyphen		0.030, 0.021	.;B;.;.;B;.;.
Vest4		0.41
MVP		0.74
MPC		0.094
ClinPred		0.80	D
GERP RS		5.5
Varity_R		0.49
gMVP		0.22

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.13
dbscSNV1_RF	Benign	0.32
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

Publications

LitVar

Other links and lift over

dbSNP: rs754152768; hg19: chr17-41201210;