rs886037742
Variant summary
Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2
The NM_000059.4(BRCA2):c.1216_1219delGCCCinsACCG(p.AlaGln406ThrGlu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. A406A) has been classified as Benign.
Frequency
Consequence
NM_000059.4 missense
Scores
Clinical Significance
Conservation
Genome browser will be placed here
ACMG classification
Verdict is Uncertain_significance. Variant got 2 ACMG points.
Transcripts
RefSeq
Ensembl
Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | TSL | MANE | Protein | Appris | UniProt |
---|---|---|---|---|---|---|---|---|---|---|
BRCA2 | ENST00000380152.8 | c.1216_1219delGCCCinsACCG | p.AlaGln406ThrGlu | missense_variant | 5 | NM_000059.4 | ENSP00000369497.3 | |||
BRCA2 | ENST00000530893.7 | c.847_850delGCCCinsACCG | p.AlaGln283ThrGlu | missense_variant | 1 | ENSP00000499438.2 | ||||
BRCA2 | ENST00000614259.2 | n.1216_1219delGCCCinsACCG | non_coding_transcript_exon_variant | Exon 9 of 26 | 2 | ENSP00000506251.1 |
Frequencies
GnomAD3 genomes Cov.: 32
GnomAD4 genome Cov.: 32
ClinVar
Submissions by phenotype
Hereditary cancer-predisposing syndrome Uncertain:1Benign:1
The c.1216_1219delGCCCinsACCG variant (also known as p.A406_Q407delinsTE), located in coding exon 9 of the BRCA2 gene, results from an in-frame deletion of GCCC and insertion of ACCG at nucleotide positions 1216 to 1219. This results in the substitution of alanine and glutamine residues for a threonine and glutamate at codon 406 and 407. This amino acid region is not well conserved in available vertebrate species. In addition, this alteration is predicted to be neutral by in silico analysis (Choi Y et al. PLoS ONE. 2012; 7(10):e46688). Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
Missense variant in a coldspot region where missense variants are very unlikely to be pathogenic (PMID:31911673). -
not specified Uncertain:1
Variant summary: BRCA2 c.1216_1219delinsACCG (p.Ala406_Gln407delinsThrGlu) results in an in-frame deletion-insertion that that replaces two adjacent amino acids (alanine and glutamine) at codons 406-407 with two different amino acids (threonine and glutamic acid). This variant is reported as two separate single-nucleotide changes (i.e. c.1216G>A (p.Ala406Thr) and c.1219C>G (p. Gln407Glu)) in the gnomAD database, however read data indicate that these variants were found in cis, therefore the variant allele is likely found at a frequency of 1.1e-05 in ~281500 control chromosomes. The variant was absent in 281524 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. The c.1216G>A and c.1219C>G variants have been reported together in multiple cohorts of individuals who had personal and/or family history of breast/ovarian cancer (Caux-Moncoutier_2011, Alsop_2012, Dorling_2021). However, these reports do not specify whether the two variants were observed together in the same individuals or separately in different individuals. A recent study reported the two component variants (c.1216G>A and c.1219C>G) in an endometrioid adenocarcinoma patient (Akaev_2021), however the phase of these variants was not specified. On the other hand, a co-occurrence of the c.1216G>A and c.1219C>G variants (phase not specified) with another pathogenic variant (BRCA2 c.3599_3600del (p.Cys1200X); in LOVD) has also been reported in a breast cancer patient, providing supporting evidence for a benign role. Furthermore, one study reported the variant c.1216_1219delinsACCG in an ovarian cancer patient (Hauke_2020). To our knowledge, no experimental evidence demonstrating its impact on protein function have been reported. Three clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014, and all of them classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -
Breast-ovarian cancer, familial, susceptibility to, 2 Uncertain:1
The BRCA2 p.Ala406_Gln407delinsThrGlu variant was not identified in the literature nor was it identified in the LOVD 3.0 or UMD-LSDB databases. The variant was identified in dbSNP (ID: rs886037742) as "With Uncertain significance allele" and ClinVar (classified as uncertain significance by GeneDx and Invitae). The variant was not identified in the following control databases: the Exome Aggregation Consortium (August 8th 2016) or the Genome Aggregation Database (Feb 27, 2017). This variant is an in-frame deletion-insertion resulting in the removal of an Alanine (Ala) residue at codon 406 and Glutamine (Gln) residue at codon 407 and insertion of Threonine (Thr) and Glutamate (Glu); the impact of this alteration on BRCA2 protein function is not known. In silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer) do not predict a greater than 10% 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 provided Uncertain:1
In-frame deletion and insertion of four amino acids in a non-repeat region; Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this variant does not alter protein structure/function; Also known as 1444_1447delGCCCinsACCG; This variant is associated with the following publications: (PMID: 33808557, 33273034, 33471991, 22711857, 21120943) -
Hereditary breast ovarian cancer syndrome Uncertain:1
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. This is a complex sequence change that replaces alanine and glutamine with threonine and glutamic acid at codons 406-407 of the BRCA2 protein (p.Ala406_Gln407delinsThrGlu). This variant is reported as two separate single-nucleotide changes in population databases (c.1216G>A, ExAC 0.001% and c.1219C>G, ExAC 0.001%). However, in the read data for the two individuals displayed in the ExAC browser, these two variants are in cis. This recapitulates the variant observed here (c.1216_1219delinsACCG) and indicates that this variant is very likely present in the population databases at 0.001%. The p.Ala406Thr and p.Gln407Glu variants have been reported in individuals affected with hereditary breast and/or ovarian cancer (PMID: 21120943, 22711857) and also co-occurred with a BRCA2 pathogenic allele in an individual with breast cancer in the Leiden Open-source Variation Database (PMID: 21520333). However, these publications do not specify whether the two variants were observed together in a single individual or separately in different individuals. ClinVar contains an entry for this variant (Variation ID: 182308). Experimental studies and prediction algorithms are not available for this variant, and the functional significance of the disrupted amino acids is currently unknown. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at