17-43049194-T-C

Variant names:

• chr17-43049194-T-C
• rs80357041
• NM_007294.4:c.5333A>G

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 4P and 1B. PM1 PM5 BP6

The NM_007294.4(BRCA1):​c.5333A>G​(p.Asp1778Gly) variant causes a missense, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000682 in 1,613,702 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. D1778E) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 31)
  • Exomes 𝑓: 0.0000062 (0 hom.)
• Consequence: BRCA1 NM_007294.4 missense, splice_region
• Scores: Splicing: ADA: 0.0002381
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2 B:12
• Conservation: PhyloP100: 0.802
• Publications: 28 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: Uncertain_significance. The variant received 3 ACMG points.

• PM1: In a hotspot region, there are 11 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 17 benign, 79 uncertain in NM_007294.4
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr17-43051062-CCT-ATGTTG is described in ClinVar as Pathogenic. ClinVar VariationId is 236263.Status of the report is reviewed_by_expert_panel, 3 stars.
• BP6: Variant 17-43049194-T-C is Benign according to our data. Variant chr17-43049194-T-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 55539.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BRCA1	NM_007294.4	c.5333A>G	p.Asp1778Gly	missense_variant, splice_region_variant	Exon 21 of 23	ENST00000357654.9	NP_009225.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BRCA1	ENST00000357654.9	c.5333A>G	p.Asp1778Gly	missense_variant, splice_region_variant	Exon 21 of 23	1	NM_007294.4	ENSP00000350283.3

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152146 Hom.: 0 Cov.: 31

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

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: 0.0000294

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251416 AF XY: 0.00000736

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000616 AC: 9 AN: 1461556 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 727112

African (AFR) AF: 0.00 AC: 0 AN: 33472

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

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86248

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53416

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

European-Non Finnish (NFE) AF: 0.00000720 AC: 8 AN: 1111706

Other (OTH) AF: 0.0000166 AC: 1 AN: 60386

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152146 Hom.: 0 Cov.: 31 AF XY: 0.0000135 AC XY: 1 AN XY: 74328

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 41428

American (AMR) AF: 0.00 AC: 0 AN: 15262

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5192

South Asian (SAS) AF: 0.00 AC: 0 AN: 4832

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10614

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000294 AC: 2 AN: 68032

Other (OTH) AF: 0.00 AC: 0 AN: 2088

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0.00000000770867), which strongly suggests a high chance of mosaicism in these individuals.

Alfa AF: 0.0000249 Hom.: 0

Bravo AF: 0.0000189

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:2 Benign:12

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Breast-ovarian cancer, familial, susceptibility to, 1 Uncertain:2 Benign:3

Mar 22, 2017

Counsyl

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com.

May 25, 2021

Baylor Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was determined to be of uncertain significance according to ACMG Guidelines, 2015 [PMID:25741868].

Jul 26, 2010

Sharing Clinical Reports Project (SCRP)

Significance: Benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

May 29, 2002

Breast Cancer Information Core (BIC) (BRCA1)

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: clinical testing

Jan 11, 2024

All of Us Research Program, National Institutes of Health

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Hereditary cancer-predisposing syndrome Benign:3

May 02, 2017

Color Diagnostics, LLC DBA Color Health

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Sep 08, 2021

Sema4, Sema4

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: curation

Dec 08, 2014

Ambry Genetics

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This alteration is classified as 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.

not specified Benign:2

Nov 02, 2021

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

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: BRCA1 c.5333A>G (p.Asp1778Gly) results in a non-conservative amino acid change located in the BRCT domain of the encoded protein sequence. Three of five in-silico tools predict a benign effect of the variant on protein function and 4/4 computational tools predict no significant impact on normal splicing. The variant allele was found at a frequency of 4e-06 in 251416 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.5333A>G has been reported in the literature in individuals affected with Breast And Ovarian Cancer (Judkins_2005, Thomassen_2011, Colombo_2013, Tommasi_2005, Santonocito_2020, Dorling_2021). In families with this variant, 2 transmissions of the variant allele and 1 transmissions of the reference allele to affected individuals was reported (Colombo_2013, Santonocito_2013), however in one reported family this variant was found in the proband but not found in the affected mother, suggesting a possible lack of cosegregation which is evidence against pathogenicity (Colombo_2013). In a recent case-control study, the results showed that this variant does not associate with breast cancer (Dorling_2021). At least eight publications report experimental evidence evaluating an impact on protein function and showed no damaging effect of this variant. Six 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 benign/likely benign. Based on the evidence outlined above, the variant was classified as benign.

Sep 15, 2017

GeneDx

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease.

not provided Benign:1

Aug 22, 2023

Quest Diagnostics Nichols Institute San Juan Capistrano

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Malignant tumor of breast Benign:1

Department of Pathology and Laboratory Medicine, Sinai Health System

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

The BRCA1 p.Asp1778Gly variant was identified in 2 of 266 proband chromosomes (frequency 0.008) from individuals with breast cancer (Thomassen 2012, Tommasi 2005), and was also reported by our lab in an Italian individual with breast cancer. The variant was identified in dbSNP (ID: rs80357041) “With unknown allele” but no frequency information was provided, so the prevalence of this variant in the general population is not known. The variant was classified as a benign variant by the Sharing Clinical Reports Project (SCRP) (submitted within the ClinVar database and derived from Myriad reports). The variant was also reported in HGMD, LOVD, once in the UMD as an unclassified variant, and once in the BIC database with unknown clinical importance. The p.Asp1778Gly variant occurs in the first base of the exon; this position has been shown to be part of the splicing consensus sequence and variants involving this position sometimes affect splicing; however, in silico or computational prediction software (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer, HumanSpliceFinder) yielded inconsistent predictions of this variant on splicing and this information is not very predictive of pathogenicity. Two studies using RT-PCR analysis of the variant found no aberrant changes to the BRCA1 mRNA transcript, indicating that this variant exhibits normal splicing (Colombo 2012, Thomassen 2012). The p.Asp1778 residue is conserved in mammals but not in lower organisms, with the variant amino acid Glycine (Gly) present in chicken, increasing the likelihood that this variant may not have clinical significance. Computational analyses (PolyPhen-2, SIFT, AlignGVGD, BLOSUM) provide inconsistent predictions regarding the impact to the protein and this information is not very predictive of pathogenicity. The results of studies assessing the impact of the variant on the protein are conflicting: a study by Mirkovic (2004) using in silico protein structure modeling predicts this variant to be deleterious; however, algorithms developed by Karchin (2007) predict this variant to be neutral, and a functional study by Lee (2010) found no effect of this variant on BRCA1 protein stability, protein binding and transcriptional activity. In summary, based on the above information, the clinical significance of this variant cannot be determined with certainty at this time although we would lean towards a more benign role for this variant. This variant is classified as predicted benign.

BRCA1-related disorder Benign:1

Jan 11, 2024

PreventionGenetics, part of Exact Sciences

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications).

Hereditary breast ovarian cancer syndrome Benign:1

Jan 15, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.13
BayesDel_addAF	Uncertain	0.071	D
BayesDel_noAF	Uncertain	0.050
CADD	Benign	21
DANN	Benign	0.97
DEOGEN2	Benign	0.0	.;T;.;T;T;.;.
Eigen	Benign	-0.20
Eigen_PC	Benign	-0.11
FATHMM_MKL	Uncertain	0.78	D
LIST_S2	Uncertain	0.86	D;D;D;D;D;D;D
M_CAP	Pathogenic	0.59	D
MetaRNN	Uncertain	0.65	D;D;D;D;D;D;D
MetaSVM	Benign	-0.41	T
MutationAssessor	Benign	0.0	.;L;.;.;.;.;.
PhyloP100		0.80
PrimateAI	Benign	0.38	T
PROVEAN	Pathogenic	-4.6	D;N;.;.;.;N;D
REVEL	Uncertain	0.56
Sift	Benign	0.072	T;D;.;.;.;D;T
Sift4G	Benign	0.17	T;T;T;T;T;T;T
Vest4		0.48
ClinPred		0.45	T
GERP RS		4.4
Varity_R		0.57
gMVP		0.54
Mutation Taster		=44/56	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.00024
dbscSNV1_RF	Benign	0.0020
Splicevardb		1.0
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

Other links and lift over

dbSNP: rs80357041; hg19: chr17-41201211;