chr13-32336675-A-G

Variant names:

• chr13-32336675-A-G
• rs55968715
• NM_000059.4:c.2320A>G

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP4_Strong BP6

The NM_000059.4(BRCA2):​c.2320A>G​(p.Thr774Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000428 in 1,613,754 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/20 in silico tools predict a benign outcome for this variant. 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. T774N) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.000053 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000042 (0 hom.)
• Consequence: BRCA2 NM_000059.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:4 B:14 O:1
• Conservation: PhyloP100: -0.352
• Publications: 18 publications found

Genes affected

BRCA2 (HGNC:1101): (BRCA2 DNA repair associated) Inherited mutations in BRCA1 and this gene, BRCA2, confer increased lifetime risk of developing breast or ovarian cancer. Both BRCA1 and BRCA2 are involved in maintenance of genome stability, specifically the homologous recombination pathway for double-strand DNA repair. The largest exon in both genes is exon 11, which harbors the most important and frequent mutations in breast cancer patients. The BRCA2 gene was found on chromosome 13q12.3 in human. The BRCA2 protein contains several copies of a 70 aa motif called the BRC motif, and these motifs mediate binding to the RAD51 recombinase which functions in DNA repair. BRCA2 is considered a tumor suppressor gene, as tumors with BRCA2 mutations generally exhibit loss of heterozygosity (LOH) of the wild-type allele. [provided by RefSeq, May 2020]

BRCA2 Gene-Disease associations (from GenCC):

• breast-ovarian cancer, familial, susceptibility to, 2

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), ClinGen
• Fanconi anemia complementation group D1

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, ClinGen, G2P
• pancreatic cancer, susceptibility to, 2

  Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
• sarcoma

  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
• medulloblastoma

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics

ACMG classification

Our verdict: Likely_benign. The variant received -5 ACMG points.

• BP4: Computational evidence support a benign effect (MetaRNN=0.05243364).
• BP6: Variant 13-32336675-A-G is Benign according to our data. Variant chr13-32336675-A-G is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 37781.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000059.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	BRCA2	NM_000059.4	MANE Select	c.2320A>G	p.Thr774Ala	missense	Exon 11 of 27	NP_000050.3
	BRCA2	NM_001432077.1		c.2320A>G	p.Thr774Ala	missense	Exon 11 of 27	NP_001419006.1
	BRCA2	NM_001406720.1		c.2320A>G	p.Thr774Ala	missense	Exon 11 of 27	NP_001393649.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	BRCA2	ENST00000380152.8	TSL:5 MANE Select	c.2320A>G	p.Thr774Ala	missense	Exon 11 of 27	ENSP00000369497.3
	BRCA2	ENST00000544455.6	TSL:1	c.2320A>G	p.Thr774Ala	missense	Exon 11 of 27	ENSP00000439902.1
	BRCA2	ENST00000530893.7	TSL:1	c.1951A>G	p.Thr651Ala	missense	Exon 11 of 27	ENSP00000499438.2

Frequencies

GnomAD3 genomes AF: 0.0000526 AC: 8 AN: 152194 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000131

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: 0.0000882

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.0000398 AC: 10 AN: 250976 AF XY: 0.0000516

Gnomad AFR exome AF: 0.0000616

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: 0.0000706

Gnomad OTH exome AF: 0.000164

GnomAD4 exome AF: 0.0000417 AC: 61 AN: 1461560 Hom.: 0 Cov.: 33 AF XY: 0.0000440 AC XY: 32 AN XY: 727084

African (AFR) AF: 0.0000299 AC: 1 AN: 33472

American (AMR) AF: 0.00 AC: 0 AN: 44708

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26128

East Asian (EAS) AF: 0.00 AC: 0 AN: 39678

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86252

European-Finnish (FIN) AF: 0.0000562 AC: 3 AN: 53390

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.0000486 AC: 54 AN: 1111782

Other (OTH) AF: 0.0000331 AC: 2 AN: 60384

GnomAD4 genome AF: 0.0000526 AC: 8 AN: 152194 Hom.: 0 Cov.: 32 AF XY: 0.0000538 AC XY: 4 AN XY: 74352

African (AFR) AF: 0.00 AC: 0 AN: 41442

American (AMR) AF: 0.000131 AC: 2 AN: 15270

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5208

South Asian (SAS) AF: 0.00 AC: 0 AN: 4830

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: 0.0000882 AC: 6 AN: 68038

Other (OTH) AF: 0.00 AC: 0 AN: 2094

Alfa AF: 0.0000799 Hom.: 0

Bravo AF: 0.0000793

ESP6500AA AF: 0.00 AC: 0

ESP6500EA AF: 0.000116 AC: 1

ExAC AF: 0.0000412 AC: 5

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:4 Benign:14 Other:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

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

Feb 12, 2016

Counsyl

Significance: Uncertain significance

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.

Sep 01, 2023

Department of Medical and Surgical Sciences, University of Bologna

Significance: Benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

BS1(Supporting)+BP1(Strong)+BP5(Moderate) according to ACMG/AMP classification guidelines specified for BRCA1 & BRCA2 (Classification Criteria V1.0.0 2023-09-08 - https://cspec.genome.network/cspec/ui/svi/affiliation/50087) (PMID: 38160042)

Apr 21, 2016

Michigan Medical Genetics Laboratories, University of Michigan

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Nov 19, 2009

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) (BRCA2)

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: clinical testing

Hereditary cancer-predisposing syndrome Benign:5

Aug 18, 2021

Sema4, Sema4

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: curation

Nov 19, 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.

Aug 01, 2016

Color Diagnostics, LLC DBA Color Health

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Jul 12, 2017

True Health Diagnostics

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

Mar 23, 2023

University of Washington Department of Laboratory Medicine, University of Washington

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: curation

Missense variant in a coldspot region where missense variants are very unlikely to be pathogenic (PMID:31911673).

not specified Benign:3 Other:1

Sep 19, 2013

ITMI

Significance: not provided

Review Status: no classification provided

Collection Method: reference population

Feb 07, 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: BRCA2 c.2320A>G (p.Thr774Ala) results in a non-conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 4e-05 in 250976 control chromosomes, predominantly at a frequency of 7.1e-05 within the Non-Finnish European subpopulation in the gnomAD database. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.2320A>G has been reported in the literature in individuals affected with Breast or Prostate cancer and Ovarian Cancer as well as in a patient with macrocytic thrombocytopenia (example, Haiman_2013, Cunningham_2014, Kager_2018). These report(s) do not provide unequivocal conclusions about association of the variant with Hereditary Breast And Ovarian Cancer Syndrome. Multiple co-occurrences with other pathogenic variant(s) have been reported in public databases such as UMD and BIC as well as our laboratory (UMD-BRCA2 c.5576_5579delTTAA, p.Ile1859fsX3; BRCA1 c.3700_3704delGTAAA, p.Val1234GlnfsX8; BRCA1 c.4065_4068delTCAA, p.Asn1355LysfsX10; BIC-BRCA1 c.3255_3256insGA, p.Arg1085_Leu1086?fs; Our laboratory-BRCA1 c.2722G>T, p.Glu908X), providing supporting evidence for a benign role. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Seven clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation (likely benign/benign, n=6; VUS, n=1). Based on the evidence outlined above, the variant was classified as benign.

Department of Pathology and Laboratory Medicine, Sinai Health System

Significance: Benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

The BRCA2 p.Thr774Ala variant was not identified in the literature. The variant was identified in dbSNP (ID: rs55968715), the ClinVar database (classified as a benign variant by Ambry Genetics and by the Sharing Clinical Reports Project (derived from Myriad reports)), the BIC database (6X with unknown clinical importance), and UMD (3X as an unclassified variant). In UMD the variant was identified in one sample with a co-occurring pathogenic BRCA2 variant (c.5576_5579delTTAA (p.Ile1859LysfsX3)) and in another sample with a co-occurring pathogenic BRCA1 variant (c.4065_4068delTCAA (p.Asn1355LysfsX10), increasing the likelihood that the p.Thr774Ala variant does not have clinical significance. The variant was identified by the Exome Variant Server project in 1 of 8600 European American alleles (frequency: 0.0001), although this low number of observations and low frequency is not substantive enough to determine the prevalence of the variant in the general population and its relationship to disease. The p.Thr774 residue is not conserved in mammals and computational analyses (PolyPhen-2, SIFT, AlignGVGD, BLOSUM, MutationTaster) do not suggest a high likelihood of impact to the protein. In addition, the variant occurs outside of the splicing consensus sequence and in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer, HumanSpliceFinder) do not predict a difference in splicing. However, this information is not predictive enough to rule out pathogenicity. In summary, based on the above information, this variant meets our laboratory's criteria to be classified as benign.

Jul 02, 2018

ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Hereditary breast ovarian cancer syndrome Uncertain:1 Benign:1

Jan 13, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Nov 09, 2021

Institute for Biomarker Research, Medical Diagnostic Laboratories, L.L.C.

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: clinical testing

not provided Benign:2

Aug 06, 2019

GeneDx

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is associated with the following publications: (PMID: 24817641, 24728327, 24504028, 25348012, 27633797, 23555315)

Apr 01, 2024

CeGaT Center for Human Genetics Tuebingen

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

BRCA2: BP4

BRCA2-related disorder Uncertain:1

Oct 09, 2023

PreventionGenetics, part of Exact Sciences

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The BRCA2 c.2320A>G variant is predicted to result in the amino acid substitution p.Thr774Ala. This variant has been reported in an individual with congenital macrocytic thrombocytopenia that also harbored a variant in another gene (Kager et al. 2018. PubMed ID: 29797310, Supplemental data, Patient 13), an individual with ovarian cancer (Cunningham et al. 2014. PubMed ID: 24504028, Table S1), and multiple individuals in the Breast Information Core (BIC) database (Szabo et al. 2000. PubMed ID: 10923033, https://research.nhgri.nih.gov/projects/bic; Breast Cancer Association Consortium et al. 2021. PubMed ID: 33471991). It has also been reported in a cohort of healthy adults (Bodian et al. 2014. PubMed ID: 24728327, Table S1, referred to as rs55968715; Breast Cancer Association Consortium et al. 2021. PubMed ID: 33471991). This variant is reported in 0.0071% of alleles in individuals of European (Non-Finnish) descent in gnomAD (http://gnomad.broadinstitute.org/variant/13-32910812-A-G) and has conflicting interpretations of benign, likely benign, and uncertain significance in ClinVar (https://www.ncbi.nlm.nih.gov/clinvar/variation/37781). Although we suspect that this variant may be benign, at this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.062
BayesDel_addAF	Benign	-0.27	T
BayesDel_noAF	Benign	-0.44
CADD	Benign	0.078
DANN	Benign	0.27
Eigen	Benign	-1.8
Eigen_PC	Benign	-1.8
FATHMM_MKL	Benign	0.017	N
M_CAP	Benign	0.018	T
MetaRNN	Benign	0.052	T
MetaSVM	Benign	-1.1	T
PhyloP100		-0.35
PrimateAI	Benign	0.22	T
PROVEAN	Benign	-0.53	N
REVEL	Benign	0.16
Sift	Benign	0.13	T
Sift4G	Benign	0.45	T
Vest4		0.088
MVP		0.66
MPC		0.022
ClinPred		0.045	T
GERP RS		-7.5
gMVP		0.13
Mutation Taster		=91/9	polymorphism

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

Other links and lift over

dbSNP: rs55968715; hg19: chr13-32910812; COSMIC: COSV99061626;