17-61744531-C-T

Position:

• chr17-61744531-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_032043.3(BRIP1):​c.2158G>A​(p.Val720Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,610 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: BRIP1 NM_032043.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:4 B:1
• Conservation: PhyloP100: 0.634

Genes affected

BRIP1 (HGNC:20473): (BRCA1 interacting helicase 1) The protein encoded by this gene is a member of the RecQ DEAH helicase family and interacts with the BRCT repeats of breast cancer, type 1 (BRCA1). The bound complex is important in the normal double-strand break repair function of breast cancer, type 1 (BRCA1). This gene may be a target of germline cancer-inducing mutations. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BRIP1	NM_032043.3	c.2158G>A	p.Val720Met	missense_variant	15/20	ENST00000259008.7	NP_114432.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BRIP1	ENST00000259008.7	c.2158G>A	p.Val720Met	missense_variant	15/20	1	NM_032043.3	ENSP00000259008	P2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461610 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727122

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4 Benign:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Apr 09, 2019	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Jan 03, 2023	The p.V720M variant (also known as c.2158G>A), located in coding exon 14 of the BRIP1 gene, results from a G to A substitution at nucleotide position 2158. The valine at codon 720 is replaced by methionine, an amino acid with highly similar properties. This amino acid position is not well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Familial cancer of breast;C1836860:Fanconi anemia complementation group J Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jul 08, 2023

Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt BRIP1 protein function. This sequence change replaces valine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 720 of the BRIP1 protein (p.Val720Met). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with BRIP1-related conditions. ClinVar contains an entry for this variant (Variation ID: 491433). 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. -

Familial cancer of breast Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Baylor Genetics

Aug 02, 2023

- -

Malignant tumor of breast Benign:1

Likely benign, no assertion criteria provided

clinical testing

Department of Pathology and Laboratory Medicine, Sinai Health System

-

The BRIP1 p.Val720Met variant was not identified in the literature nor was it identified in the dbSNP, ClinVar, Cosmic, MutDB, Zhejiang Colon Cancer Databases. The variant was not identified in the 1000 Genomes Project, the NHLBI GO Exome Sequencing Project or the Exome Aggregation Consortium (August 8th 2016) control databases. The p.Val720 residue is conserved in mammals but not in more distantly related organisms however four out of five computational analyses (PolyPhen-2, SIFT, AlignGVGD, BLOSUM, MutationTaster) do not suggest a high likelihood of impact to the protein; this information is not predictive enough to rule out pathogenicity. The variant occurs outside of the splicing consensus sequence and 1 of 5 in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer, HumanSpliceFinder) predict a greater than 10% difference in splicing; this is not very predictive of pathogenicity. The variant is located with the DNA helicase (DNA repair), Rad3 type Helicase, ATP-dependent, c2 type functional domain(s) increasing the likelihood that it may have clinical significance. A co-occurring pathogenic BRCA1 variant (c.709G>T, p.Glu237X) is identified in 1 individual with breast cancer in our laboratory, increasing the likelihood that p.Val720Met variant does not have clinical significance. 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 likely benign. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.12
BayesDel_addAF	Uncertain	0.052	T
BayesDel_noAF	Benign	-0.16
CADD	Benign	23
DANN	Benign	0.95
DEOGEN2	Uncertain	0.49	T;.
Eigen	Uncertain	0.28
Eigen_PC	Uncertain	0.25
FATHMM_MKL	Benign	0.69	D
LIST_S2	Benign	0.78	T;T
M_CAP	Uncertain	0.21	D
MetaRNN	Uncertain	0.43	T;T
MetaSVM	Uncertain	0.69	D
MutationAssessor	Uncertain	2.9	M;M
MutationTaster	Benign	0.57	N;N
PrimateAI	Benign	0.43	T
PROVEAN	Benign	-0.76	N;.
REVEL	Uncertain	0.43
Sift	Benign	0.099	T;.
Sift4G	Benign	0.19	T;T
Polyphen		0.83	P;.
Vest4		0.38
MutPred		0.44		Loss of sheet (P = 0.0126);Loss of sheet (P = 0.0126);
MVP		0.97
MPC		0.38
ClinPred		0.73	D
GERP RS		3.5
Varity_R		0.13
gMVP		0.46

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: rs1555591459; hg19: chr17-59821892;