Our verdict is Benign. The variant received -10 ACMG points: 2P and 12B. PM2BP4_StrongBP6_Very_Strong
The NM_007294.4(BRCA1):c.441+17T>C variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).
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]
BRCA1 Gene-Disease associations (from GenCC):
breast-ovarian cancer, familial, susceptibility to, 1
Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, ClinGen, Labcorp Genetics (formerly Invitae), Genomics England PanelApp
Our verdict: Benign. The variant received -10 ACMG points.
PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.87).
BP6
Variant 17-43104105-A-G is Benign according to our data. Variant chr17-43104105-A-G is described in ClinVar as [Likely_benign]. Clinvar id is 182089.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
Data not reliable, filtered out with message: AS_VQSR
AF:
6.87e-7
AC:
1
AN:
1456548
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
724490
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.0000302
AC:
1
AN:
33154
American (AMR)
AF:
0.00
AC:
0
AN:
44094
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26050
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39660
South Asian (SAS)
AF:
0.00
AC:
0
AN:
85022
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53062
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5740
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1109584
Other (OTH)
AF:
0.00
AC:
0
AN:
60182
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.375
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Age Distribution
Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
Cov.:
32
Alfa
AF:
0.000310
Hom.:
0
Bravo
AF:
0.000423
ClinVar
Significance: Benign/Likely benign
Submissions summary: Benign:5
Revision: criteria provided, multiple submitters, no conflicts
This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -
Dec 19, 2019
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing
Variant summary: BRCA1 c.441+17T>C alters a non-conserved nucleotide located close to a canonical splice site and therefore could affect mRNA splicing, leading to a significantly altered protein sequence. 5/5 computational tools predict no significant impact on normal splicing. However, these predictions have yet to be confirmed by functional studies. The variant was absent in 246020 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.441+17T>C has not been reported in individuals affected with Hereditary Breast and Ovarian Cancer, however has been reported in one healthy individual, age not specified (Meghani 2016). This report does not provide unequivocal conclusions about association of the variant with Hereditary Breast and Ovarian Cancer. Co-occurrences with other pathogenic variants have been reported in our internal database (BRCA2 c.9253dupA, p.Thr3085fsX26; CHEK2 c.1100delC, p.Thr367fsX15; BRCA1 c.3340G>T, p.Glu1114X), providing supporting evidence for a benign role. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Three ClinVar submitter (evaluation after 2014) cite the variant as likely benign. Based on the evidence outlined above, the variant was classified as benign. -
Breast-ovarian cancer, familial, susceptibility to, 1Benign:1
Jul 29, 2016
Counsyl
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing
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. -