chr17-43082422-G-GTTCT

Position:

• chr17-43082422-G-GTTCT

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_007294.4(BRCA1):​c.4338_4339insAGAA​(p.Gln1447ArgfsTer16) variant causes a frameshift 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 Pathogenic (★★★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: BRCA1 NM_007294.4 frameshift
• Clinical Significance: Pathogenic reviewed by expert panel P:9
• Conservation: PhyloP100: 0.0880

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]

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 17-43082422-G-GTTCT is Pathogenic according to our data. Variant chr17-43082422-G-GTTCT is described in ClinVar as [Pathogenic]. Clinvar id is 55172.Status of the report is reviewed_by_expert_panel, 3 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BRCA1	NM_007294.4	c.4338_4339insAGAA	p.Gln1447ArgfsTer16	frameshift_variant	12/23	ENST00000357654.9	NP_009225.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BRCA1	ENST00000357654.9	c.4338_4339insAGAA	p.Gln1447ArgfsTer16	frameshift_variant	12/23	1	NM_007294.4	ENSP00000350283	P4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:9

Revision: reviewed by expert panel

Submissions by phenotype

Hereditary breast ovarian cancer syndrome Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Jun 15, 2018	Variant summary: BRCA1 c.4335_4338dupAGAA (p.Gln1447ArgfsX16) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. Truncations downstream of this position have been classified as pathogenic by our laboratory (e.g., p.Pro1464fsX2 and p.Ser1503X). The variant was absent in 246144 control chromosomes. c.4335_4338dupAGAA has been reported in the literature in several individuals affected with Hereditary Breast and Ovarian Cancer. These data indicate that the variant is likely to be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Five clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 and all classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Oct 12, 2022	This variant is not present in population databases (gnomAD no frequency). For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 55172). This variant is also known as c.4338_4339insAGAA p.Gln1447Argfs*16. This premature translational stop signal has been observed in individual(s) with breast and/or ovarian cancer (PMID: 22798144, 28724667, 30287823). This sequence change creates a premature translational stop signal (p.Gln1447Argfs*16) in the BRCA1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in BRCA1 are known to be pathogenic (PMID: 20104584). -
Pathogenic, criteria provided, single submitter	clinical testing	Department of Pathology and Laboratory Medicine, Sinai Health System	-	- -

Breast-ovarian cancer, familial, susceptibility to, 1 Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA), c/o University of Cambridge	Oct 02, 2015	- -
Pathogenic, reviewed by expert panel	curation	Evidence-based Network for the Interpretation of Germline Mutant Alleles (ENIGMA)	Sep 08, 2016	Variant allele predicted to encode a truncated non-functional protein. -

Hereditary cancer-predisposing syndrome Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	Feb 22, 2016	The c.4335_4338dupAGAA pathogenic mutation, located in coding exon 11 of the BRCA1 gene, results from a duplication of AGAA at nucleotide position 4335, causing a translational frameshift with a predicted alternate stop codon. This pathogenic mutation was identified in two Korean individuals diagnosed with breast cancer and met clinical criteria for hereditary breast and ovarian cancer (HBOC) syndrome (Kim H et al. Breast Cancer Res Treat. 2012 Aug;134(3):1315-26). In addition to the clinical data presented in the literature, since frameshifts are typically deleterious in nature, this alteration is interpreted as a disease-causing mutation (ACMG Recommendations for Standards for Interpretation and Reporting of Sequence Variations. Revision 2007. Genet Med. 2008;10:294). -
Pathogenic, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Aug 17, 2020	This variant inserts 4 nucleotides in exon 12 of the BRCA1 gene, creating a frameshift and premature translation stop signal. This variant is also known as 4454dupAGAA and c.4338_4339insAGAA in the literature. This variant is expected to result in an absent or non-functional protein product. To our knowledge, functional studies have not been reported for this variant. This variant has been reported in multiple East Asian individuals affected with breast cancer (PMID: 22798144, 25863477, 28724667, 29673794, 30287823). This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). Loss of BRCA1 function is a known mechanism of disease (clinicalgenome.org). Based on the available evidence, this variant is classified as Pathogenic. -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Dec 06, 2016

This duplication of 4 nucleotides in BRCA1 is denoted c.4335_4338dupAGAA at the cDNA level and p.Gln1447ArgfsX16 (Q1447RfsX16) at the protein level. The normal sequence, with the bases that are duplicated in brackets, is ATCC[dupAGAA]CAAA. The duplication causes a frameshift, which changes a Glutamine to an Arginine at codon 1447, and creates a premature stop codon at position 16 of the new reading frame. This variant is predicted to cause loss of normal protein function through either protein truncation or nonsense-mediated mRNA decay. BRCA1 c.4335_4338dupAGAA, previously reported as BRCA1 4454dup4, has been identified in several Korean breast/ovarian cancer patients (Kim 2012, Kang 2015). We consider this variant to be pathogenic. -

Gastric cancer Pathogenic:1

Pathogenic, no assertion criteria provided

research

Laboratory for Genotyping Development, RIKEN

Jul 01, 2021

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Computational scores

Source: dbNSFP v4.3

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs397509164; hg19: chr17-41234439;