rs80356857

Positions:

• chr17-43090944-C-A
• chr17-43090944-C-G
• chr17-43090944-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_007294.4(BRCA1):​c.4185G>T​(p.Gln1395His) variant causes a missense, splice region change. The variant was absent in control chromosomes in GnomAD project. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★). Another nucleotide change resulting in same amino acid change has been previously reported as Likely pathogenicin ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. Q1395R) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: BRCA1 NM_007294.4 missense, splice_region
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 4.83

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 Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
BRCA1	NM_007294.4	c.4185G>T	p.Gln1395His	missense_variant, splice_region_variant	11/23	ENST00000357654.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
BRCA1	ENST00000357654.9	c.4185G>T	p.Gln1395His	missense_variant, splice_region_variant	11/23	1	NM_007294.4	P4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1456042 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 723664

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

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:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hereditary breast ovarian cancer syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Mar 04, 2021

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 variant disrupts the c.4185G nucleotide in the BRCA1 gene. Other variant(s) that disrupt this nucleotide have been determined to be pathogenic (PMID: 7493024, 12759930, 23239986, 9649133). This suggests that this nucleotide is clinically significant, and that variants that disrupt this position are likely to be disease-causing. Nucleotide substitutions within the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site, but this prediction has not been confirmed by published transcriptional studies. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C15"). This variant has not been reported in the literature in individuals with BRCA1-related conditions. This variant is not present in population databases (ExAC no frequency). This sequence change replaces glutamine with histidine at codon 1395 of the BRCA1 protein (p.Gln1395His). The glutamine residue is highly conserved and there is a small physicochemical difference between glutamine and histidine. This variant also falls at the last nucleotide of exon 11, which is part of the consensus splice site for this exon. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.68
BayesDel_addAF	Pathogenic	0.28	D
BayesDel_noAF	Pathogenic	0.17
CADD	Pathogenic	34
DANN	Uncertain	1.0
Eigen	Uncertain	0.61
Eigen_PC	Uncertain	0.61
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Uncertain	0.94	D;D;D;D;D;D;D;D;D;D
M_CAP	Uncertain	0.18	D
MetaRNN	Uncertain	0.45	T;T;T;T;T;T;T;T;T;T
MetaSVM	Benign	-0.84	T
MutationTaster	Benign	1.0	D;D;D;D;D;D;D;D;D;D;D;D;D;D
PrimateAI	Uncertain	0.53	T
PROVEAN	Uncertain	-3.4	D;N;N;D;N;D;D;N;D;D
REVEL	Uncertain	0.52
Sift	Uncertain	0.0010	D;D;D;D;D;D;D;D;D;D
Sift4G	Uncertain	0.011	D;D;D;D;D;D;.;.;D;.
Polyphen		0.95, 1.0, 1.0	.;P;.;.;.;D;.;D;.;.
Vest4		0.64
MutPred		0.24		.;Gain of glycosylation at T1393 (P = 0.0913);Gain of glycosylation at T1393 (P = 0.0913);.;.;.;.;.;.;.;
MVP		0.99
MPC		0.44
ClinPred		0.94	D
GERP RS		4.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.8
Varity_R		0.41
gMVP		0.54

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	1.0
SpliceAI score (max)		0.96		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.96		Position offset: 0

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr17-41242961;