rs273898675

chr17-43106462-G-Achr17-43106462-G-Cchr17-43106462-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM1PM2PP3

The NM_007294.4(BRCA1):c.206C>T(p.Thr69Ile) variant causes a missense change. The variant allele was found at a frequency of 0.00000126 in 1,589,614 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. T69A) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 7.0e-7 ( 0 hom. )

Consequence

BRCA1
NM_007294.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4O:1

Conservation

PhyloP100: 5.23

Variant links:

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 5 ACMG points.

PM1

In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 6 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, 0.748

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
BRCA1	NM_007294.4 linkuse as main transcript	c.206C>T	p.Thr69Ile	missense_variant	4/23	ENST00000357654.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
BRCA1	ENST00000357654.9 linkuse as main transcript	c.206C>T	p.Thr69Ile	missense_variant	4/23	1	NM_007294.4	P4	P38398-1

Frequencies

GnomAD3 genomes

AF:

0.00000658

AC:

AN:

151988

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000656

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD4 exome

AF:

6.96e-7

AC:

AN:

1437626

Hom.:

Cov.:

AF XY:

0.00000140

AC XY:

AN XY:

716362

show subpopulations

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:

9.16e-7

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000658

AC:

AN:

151988

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74232

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.0000656

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4Other:1

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Breast-ovarian cancer, familial, susceptibility to, 1

Uncertain:1Other:1

not provided, no classification provided	in vitro	Brotman Baty Institute, University of Washington	-	- -
Uncertain significance, criteria provided, single submitter	clinical testing	All of Us Research Program, National Institutes of Health	May 30, 2023	This missense variant replaces threonine with isoleucine at codon 69 of the BRCA1 protein. Computational prediction is inconclusive regarding the impact of this variant on protein structure and function (internally defined REVEL score threshold 0.5 < inconclusive < 0.7, PMID: 27666373). Functional studies have reported that this variant has no impact on BRCA1 function in a haploid cell proliferation assay and a mammalian two-hybrid assay (PMID: 30209399, 35659930). To our knowledge, this variant has not been reported in individuals affected with hereditary cancer in the literature. This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

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

Jan 03, 2022

Variant summary: BRCA1 c.206C>T (p.Thr69Ile) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 249744 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.206C>T in individuals affected with Hereditary Breast And Ovarian Cancer Syndrome has been reported. At least one publication reports experimental evidence evaluating an impact on protein function (example, Findlay_2018). These results showed no damaging effect of this variant on homology directed repair (HDR) activity. HDR assays qualify as a recognized gold standard on the basis of updated guidance provided by the ClinGen Sequence Variant Interpretation (SVI) working group. This working group has recommended strong functional evidence (ACMG BS3) as sufficient weightage for categorization as likely benign (Tavtigian_2018). Two clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as uncertain significance. As of this review, none of the submitters have cited the functional evidence utilized in the context of this evalution. Based on the evidence outlined above, pending additional peer consensus supported by co-occurrences demonstrating an alternative molecular basis of disease, the variant was classified as VUS-possibly benign. -

Hereditary cancer-predisposing syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 31, 2022

The p.T69I variant (also known as c.206C>T), located in coding exon 3 of the BRCA1 gene, results from a C to T substitution at nucleotide position 206. The threonine at codon 69 is replaced by isoleucine, an amino acid with similar properties. Based on protein sequence alignment, this amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of p.T69I remains unclear. -

Hereditary breast ovarian cancer syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Nov 20, 2022

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). This sequence change replaces threonine, which is neutral and polar, with isoleucine, which is neutral and non-polar, at codon 69 of the BRCA1 protein (p.Thr69Ile). ClinVar contains an entry for this variant (Variation ID: 441428). 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: 30209399). Advanced modeling performed at Invitae incorporating data from internal and/or published experimental studies (PMID: 30209399) indicates that this missense variant is not expected to disrupt BRCA1 function. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.96

BayesDel_addAF

Pathogenic

0.34

BayesDel_noAF

Pathogenic

0.25

Cadd

Pathogenic

Dann

Uncertain

1.0

Eigen

Pathogenic

0.70

Eigen_PC

Uncertain

0.65

FATHMM_MKL

Pathogenic

0.97

LIST_S2

Pathogenic

0.98

D;D;D;D;D;D;D;D;D;D;D;D;D;D

M_CAP

Pathogenic

0.73

MetaRNN

Pathogenic

0.75

D;D;D;D;D;D;D;D;D;D;D;D;D;D

MetaSVM

Pathogenic

0.86

MutationAssessor

Uncertain

2.4

M;M;M;M;.;M;.;.;.;.;.;.;.;.

MutationTaster

Benign

1.0

D;D;D;D;D;D;D;D;D;N;N;N;N;N

PrimateAI

Uncertain

0.76

PROVEAN

Benign

-1.7

N;N;N;N;N;N;D;N;N;.;N;N;D;.

REVEL

Uncertain

0.64

Sift

Uncertain

0.0030

D;D;D;D;D;D;D;D;D;.;D;D;D;.

Sift4G

Uncertain

0.012

D;D;D;D;D;D;.;D;D;.;D;D;.;.

Polyphen

1.0, 1.0

.;D;.;.;.;D;.;.;D;.;.;.;.;.

Vest4

0.71

MutPred

0.28

Loss of disorder (P = 0.0393);Loss of disorder (P = 0.0393);Loss of disorder (P = 0.0393);Loss of disorder (P = 0.0393);.;Loss of disorder (P = 0.0393);Loss of disorder (P = 0.0393);.;Loss of disorder (P = 0.0393);Loss of disorder (P = 0.0393);Loss of disorder (P = 0.0393);Loss of disorder (P = 0.0393);Loss of disorder (P = 0.0393);.;

MVP

0.98

MPC

0.31

ClinPred

0.97

GERP RS

4.6

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.34

gMVP

0.67

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.040

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over