17-43051115-G-T

Position:

• chr17-43051115-G-T

Variant summary

Our verdict is Benign. Variant got -9 ACMG points: 2P and 11B. PM2 BP4_Moderate BP6_Very_Strong BP7

The ENST00000357654.9(BRCA1):​c.5280C>A​(p.Ile1760=) variant causes a splice region, synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,516 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 1/1 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Likely benign (★★★). Synonymous variant affecting the same amino acid position (i.e. I1760I) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: BRCA1 ENST00000357654.9 splice_region, synonymous
• Clinical Significance: Likely benign reviewed by expert panel B:6 O:1
• Conservation: PhyloP100: 2.16

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 Benign. Variant got -9 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.32).
• BP6: Variant 17-43051115-G-T is Benign according to our data. Variant chr17-43051115-G-T is described in ClinVar as [Likely_benign]. Clinvar id is 186911.Status of the report is reviewed_by_expert_panel, 3 stars.
• BP7: Synonymous conserved (PhyloP=2.16 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BRCA1	NM_007294.4	c.5280C>A	p.Ile1760=	splice_region_variant, synonymous_variant	20/23	ENST00000357654.9	NP_009225.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BRCA1	ENST00000357654.9	c.5280C>A	p.Ile1760=	splice_region_variant, synonymous_variant	20/23	1	NM_007294.4	ENSP00000350283	P4

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461516 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727090

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 31

ClinVar

Significance: Likely benign

Submissions summary: Benign:6 Other:1

Revision: reviewed by expert panel

Submissions by phenotype

Breast-ovarian cancer, familial, susceptibility to, 1 Benign:2 Other:1

Likely benign, criteria provided, single submitter	clinical testing	All of Us Research Program, National Institutes of Health	Mar 04, 2023	- -
not provided, no classification provided	in vitro	Brotman Baty Institute, University of Washington	-	- -
Likely benign, reviewed by expert panel	curation	Evidence-based Network for the Interpretation of Germline Mutant Alleles (ENIGMA)	Jun 29, 2017	Synonymous substitution variant, with low bioinformatic likelihood to result in a splicing aberration (Splicing prior probability 0.02; http://priors.hci.utah.edu/PRIORS/). -

Hereditary cancer-predisposing syndrome Benign:2

Likely benign, criteria provided, single submitter	clinical testing	Ambry Genetics	Oct 22, 2014	This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -
Likely benign, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Sep 16, 2017	- -

not specified Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Aug 21, 2019

Variant summary: BRCA1 c.5280C>A (p.Ile1760Ile) alters a conserved nucleotide located close to a canonical splice site and therefore could affect mRNA splicing, leading to a significantly altered protein sequence. 4/4 computational tools predict no significant impact on normal splicing. However, these predictions have yet to be confirmed by functional studies. The variant was absent in 251176 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.5280C>A in individuals affected with Hereditary Breast and Ovarian Cancer and no experimental evidence demonstrating its impact on protein function have been reported. Two clinical diagnostic laboratories and one expert panel (ENIGMA) have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All submitters classified the variant as likely benign. Based on the evidence outlined above, the variant was classified as likely benign. -

Hereditary breast ovarian cancer syndrome Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Mar 03, 2022

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.32
CADD	Benign	14
DANN	Benign	0.81
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

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

Publications

LitVar

Other links and lift over

dbSNP: rs750040616; hg19: chr17-41203132;