chr17-43070973-G-T

Variant names:

• chr17-43070973-G-T
• rs80357302
• NM_007294.4:c.4941C>A

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 4P and 3B. PM1 PM2 BP4_Moderate BP6

The NM_007294.4(BRCA1):​c.4941C>A​(p.Asn1647Lys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,880 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Benign in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. N1647I) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: BRCA1 NM_007294.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2 B:4
• Conservation: PhyloP100: -0.0550
• Publications: 11 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 1 ACMG points.

• PM1: In a hotspot region, there are 8 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 25 benign, 72 uncertain in NM_007294.4
• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.1268673).
• BP6: Variant 17-43070973-G-T is Benign according to our data. Variant chr17-43070973-G-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 55325.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BRCA1	NM_007294.4	c.4941C>A	p.Asn1647Lys	missense_variant	Exon 15 of 23	ENST00000357654.9	NP_009225.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BRCA1	ENST00000357654.9	c.4941C>A	p.Asn1647Lys	missense_variant	Exon 15 of 23	1	NM_007294.4	ENSP00000350283.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461880 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727240

African (AFR) AF: 0.00 AC: 0 AN: 33480

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: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53408

Middle Eastern (MID) AF: 0.000173 AC: 1 AN: 5768

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1112010

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:2 Benign:4

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary cancer-predisposing syndrome Benign:2

Jan 18, 2019

Ambry Genetics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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.

Oct 10, 2022

Color Diagnostics, LLC DBA Color Health

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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

Nov 30, 1998

Breast Cancer Information Core (BIC) (BRCA1)

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: clinical testing

not provided Uncertain:1

Feb 26, 2014

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is denoted BRCA1 c.4941C>A at the cDNA level, p.Asn1647Lys (N1647K) at the protein level, and results in the change of an Asparagine to a Lysine (AAC>AAA). This variant was found in one study to have no protein folding defect, normal peptide binding activity and specificity, and normal trascriptional activity (Lee 2010). BRCA1 Asn1647Lys was not observed in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. This variant is a semi-conservative substitution in which a neutral polar amino acid is replaced with a positive polar one, altering a position that is only moderately conserved throughout evolution and is located in BRCT1 domain (UniProt). In silico analyses predict this variant to have a benign effect on protein structure and function. Based on the currently available information, we consider BRCA1 Asn1647Lys to be a variant of uncertain significance.

not specified Benign:1

Apr 11, 2025

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

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: BRCA1 c.4941C>A (p.Asn1647Lys) results in a non-conservative amino acid change located in the BRCT domain superfamily of the encoded protein sequence. Four of five in-silico tools predict a benign effect of the variant on protein function. The variant was absent in 251200 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. Three independent functional studies have reported no damaging effect of this variant including normal transcriptional activity (Lee_2010, Wood_2016), and functional HDR activity (Findlay_2018). The following publications have been ascertained in the context of this evaluation (PMID: 20516115, 30209399, 28781887). ClinVar contains an entry for this variant (Variation ID: 55325). Based on the evidence outlined above, the variant was classified as likely benign.

Hereditary breast ovarian cancer syndrome Benign:1

Sep 05, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.10
BayesDel_addAF	Uncertain	0.015	T
BayesDel_noAF	Benign	-0.22
CADD	Benign	6.3
DANN	Benign	0.41
DEOGEN2	Benign	0.0	.;T;.;.;T;.;.;.;T;.
Eigen	Benign	-1.1
Eigen_PC	Benign	-1.1
FATHMM_MKL	Benign	0.063	N
LIST_S2	Benign	0.77	T;T;T;T;T;T;T;T;T;T
M_CAP	Benign	0.063	D
MetaRNN	Benign	0.13	T;T;T;T;T;T;T;T;T;T
MetaSVM	Benign	-0.76	T
MutationAssessor	Benign	0.0	.;N;.;.;.;.;.;.;.;.
PhyloP100		-0.055
PrimateAI	Benign	0.39	T
PROVEAN	Benign	-1.5	N;N;.;N;.;N;N;N;N;N
REVEL	Uncertain	0.43
Sift	Benign	0.44	T;T;.;T;.;T;T;T;T;T
Sift4G	Benign	0.94	T;T;T;T;T;T;T;.;.;T
Vest4		0.27
ClinPred		0.029	T
GERP RS		-0.72
Varity_R		0.25
gMVP		0.24
Mutation Taster		=81/19	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs80357302; hg19: chr17-41222990;