chr17-61780297-G-C
Variant summary
Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM1
The NM_032043.3(BRIP1):c.1899C>G(p.Ile633Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000868 in 1,613,428 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. I633V) has been classified as Likely benign.
Frequency
Consequence
NM_032043.3 missense
Scores
Clinical Significance
Conservation
Publications
- familial ovarian cancerInheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
- Fanconi anemiaInheritance: AR Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, Illumina
- Fanconi anemia complementation group JInheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, ClinGen, Ambry Genetics, Labcorp Genetics (formerly Invitae)
- hereditary breast carcinomaInheritance: AD Classification: STRONG, LIMITED, NO_KNOWN Submitted by: ClinGen, Genomics England PanelApp, Ambry Genetics, Labcorp Genetics (formerly Invitae)
- colorectal adenomaInheritance: AD Classification: LIMITED Submitted by: Ambry Genetics
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ACMG classification
Our verdict: Uncertain_significance. The variant received 2 ACMG points.
Transcripts
RefSeq
Ensembl
Frequencies
GnomAD3 genomes AF: 0.0000197 AC: 3AN: 152104Hom.: 0 Cov.: 32 show subpopulations
GnomAD4 exome AF: 0.00000753 AC: 11AN: 1461324Hom.: 0 Cov.: 34 AF XY: 0.00000825 AC XY: 6AN XY: 727002 show subpopulations
Age Distribution
GnomAD4 genome AF: 0.0000197 AC: 3AN: 152104Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0AN XY: 74304 show subpopulations
Age Distribution
ClinVar
Submissions by phenotype
not provided Uncertain:3
Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant does not alter protein structure/function; Observed in individuals with breast cancer, ovarian cancer, or melanoma, but also in unaffected controls (Ramus et al., 2015; Easton et al., 2016; Tung et al., 2016; Pritchard et al., 2018; Dorling et al., 2021); This variant is associated with the following publications: (PMID: 26315354, 26976419, 29641532, 26921362, 33471991) -
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The BRIP1 p.Ile633Met variant was identified in 2 of 7448 proband chromosomes (frequency: 0.00023) from individuals or families with hereditary breast and ovarian cancer and was present in 1 of 6862 control chromosomes (frequency: 0.0001) from healthy individuals (Ramus 2015, Tung 2016). The variant was also identified in dbSNP (ID: rs28997572) as “With Uncertain significance allele”, ClinVar (as uncertain significance by Ambry Genetics, Invitae, and Color Genomics), Clinvitae, and Zhejiang University Database. The variant was not identified in the Cosmic or MutDB database. The variant was identified in the Exome Aggregation Consortium (August 8th 2016) control database in 1 of 121336 chromosomes at a frequency of 0.000008 in the following populations: Latino in 1 of 11578 chromosomes (freq: 0.000086), but not observed in the African, East Asian, European (Finnish), European (Non-Finnish), Other, or South Asian populations. The variant was not identified in the 1000 Genomes Project, the NHLBI GO Exome Sequencing Project, or the Genome Aggregation Database (Feb 27, 2017). The p.Ile633 residue is conserved in mammals and computational analyses (PolyPhen-2, SIFT, AlignGVGD, BLOSUM, MutationTaster) provide inconsistent predictions regarding the impact to the protein; this information is not very predictive of pathogenicity. 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. In summary, based on the above information the clinical significance of this variant cannot be determined with certainty at this time. This variant is classified as a variant of uncertain significance. -
not specified Uncertain:2
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Variant summary: BRIP1 c.1899C>G (p.Ile633Met) results in a conservative amino acid change in the encoded protein sequence. Three of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 1e-05 in 288552 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.1899C>G has been reported in the literature in individuals affected with Breast and Ovarian Cancer as well as unaffected controls (Ramus_2016, Tung_2016, Easton_2016). These report(s) do not provide unequivocal conclusions about association of the variant with Hereditary Breast and Ovarian Cancer. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Four 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. Based on the evidence outlined above, the variant was classified as uncertain significance. -
Familial cancer of breast;C1836860:Fanconi anemia complementation group J Uncertain:2
This sequence change replaces isoleucine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 633 of the BRIP1 protein (p.Ile633Met). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with BRIP1-related conditions (PMID: 26315354, 26921362, 26976419). ClinVar contains an entry for this variant (Variation ID: 231114). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) has been performed for this missense variant. However, the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on BRIP1 protein function. 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. -
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Familial cancer of breast Uncertain:2
This variant is classified as a variant of uncertain significance as there is insufficient evidence to determine its impact on protein function and/or cancer risk. -
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Hereditary cancer-predisposing syndrome Uncertain:2
The p.I633M variant (also known as c.1899C>G), located in coding exon 12 of the BRIP1 gene, results from a C to G substitution at nucleotide position 1899. The isoleucine at codon 633 is replaced by methionine, an amino acid with highly similar properties. This variant has been identified in disease cohorts including breast cancer, ovarian cancer, and cutaneous melanoma, as well as unaffected control groups across studies (Tung N et al. J Clin Oncol, 2016 May;34:1460-8; Easton DF et al. J Med Genet, 2016 05;53:298-309; Pritchard AL et al. PLoS One, 2018 Apr;13:e0194098; Dorling et al. N Engl J Med. 2021 02;384:428-439). This variant was also observed in 1/3251 individuals who met eligibility criteria for hereditary breast and ovarian cancer syndrome (Lerner-Ellis J et al. J Cancer Res Clin Oncol, 2021 Mar;147:871-879). This amino acid position is well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
This missense variant replaces isoleucine with methionine at codon 633 of the BRIP1 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with ovarian cancer (PMID: 26976419), in two individuals affected with breast cancer (PMID: 26976419), as well as two unaffected individuals (PMID: 26315354; FLOSSIES, https://whi.color.com/). 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. -
Ovarian cancer;C1836860:Fanconi anemia complementation group J Uncertain:1
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. -
Familial ovarian cancer Uncertain:1
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Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at