chr17-43051107-C-G

Position:

• chr17-43051107-C-G

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1 PM2 PP3_Moderate

The NM_007294.4(BRCA1):​c.5288G>C​(p.Gly1763Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. 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 Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G1763V) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 31)
• Consequence: BRCA1 NM_007294.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1 O:1
• Conservation: PhyloP100: 1.32

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 Likely_pathogenic. Variant got 6 ACMG points.

• PM1: In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 7 benign, 17 uncertain in NM_007294.4
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.847

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
BRCA1	NM_007294.4	c.5288G>C	p.Gly1763Ala	missense_variant	20/23	ENST00000357654.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
BRCA1	ENST00000357654.9	c.5288G>C	p.Gly1763Ala	missense_variant	20/23	1	NM_007294.4	P4

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1 Other:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

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

Aug 26, 2024

Variant summary: BRCA1 c.5288G>C (p.Gly1763Ala) results in a non-conservative amino acid change located in the BRCT domain (IPR001357) of the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 251234 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.5288G>C in individuals affected with Hereditary Breast And Ovarian Cancer Syndrome has been reported. At least one functional study reports experimental evidence evaluating an impact on protein function and showed no damaging effect of this variant on homology directed repair (HDR) activity (e.g. Findlay_2018). HDR assays qualify as a recognized gold standard on the basis of updated guidance provided by the ClinGen Sequence Variant Interpretation (SVI) working group. The following publication has been ascertained in the context of this evaluation (PMID: 30209399). ClinVar contains an entry for this variant (Variation ID: 868287). Based on the evidence outlined above, the variant was classified as uncertain significance. -

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

not provided, no classification provided

in vitro

Brotman Baty Institute, University of Washington

-

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.31
BayesDel_addAF	Pathogenic	0.27	D
BayesDel_noAF	Pathogenic	0.15
CADD	Benign	22
DANN	Uncertain	1.0
DEOGEN2	Benign	0.38	.;T;.;.;T;T;.;.
Eigen	Uncertain	0.34
Eigen_PC	Uncertain	0.34
FATHMM_MKL	Uncertain	0.87	D
LIST_S2	Uncertain	0.94	D;D;D;D;D;D;D;D
M_CAP	Pathogenic	0.56	D
MetaRNN	Pathogenic	0.85	D;D;D;D;D;D;D;D
MetaSVM	Uncertain	0.40	D
MutationAssessor	Uncertain	2.3	.;M;.;.;.;.;.;.
MutationTaster	Benign	0.88	D;D;D;D;N;N;N;N;N;N;N;N;N;N
PrimateAI	Benign	0.43	T
PROVEAN	Uncertain	-3.8	D;N;.;D;.;.;N;D
REVEL	Pathogenic	0.72
Sift	Uncertain	0.018	D;D;.;D;.;.;D;D
Sift4G	Uncertain	0.024	D;D;D;D;D;D;D;D
Polyphen		0.18, 0.99	.;B;.;.;.;D;.;.
Vest4		0.58
MVP		0.94
MPC		0.20
ClinPred		0.96	D
GERP RS		4.1
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.60
gMVP		0.66

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: rs80357007; hg19: chr17-41203124;