chr15-90784967-C-T

Variant summary

Our verdict is Benign. The variant received -11 ACMG points: 2P and 13B. PM2BP4_StrongBP6_Very_StrongBP7

The NM_000057.4(BLM):​c.2709C>T​(p.Thr903Thr) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,872 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★). Synonymous variant affecting the same amino acid position (i.e. T903T) has been classified as Likely benign.

Frequency

Genomes: not found (cov: 31)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

BLM
NM_000057.4 synonymous

Scores

2

Clinical Significance

Likely benign criteria provided, multiple submitters, no conflicts B:3

Conservation

PhyloP100: -0.203

Publications

0 publications found
Variant links:
Genes affected
BLM (HGNC:1058): (BLM RecQ like helicase) The Bloom syndrome is an autosomal recessive disorder characterized by growth deficiency, microcephaly and immunodeficiency among others. It is caused by homozygous or compound heterozygous mutation in the gene encoding DNA helicase RecQ protein on chromosome 15q26. This Bloom-associated helicase unwinds a variety of DNA substrates including Holliday junction, and is involved in several pathways contributing to the maintenance of genome stability. Identification of pathogenic Bloom variants is required for heterozygote testing in at-risk families. [provided by RefSeq, May 2020]
BLM Gene-Disease associations (from GenCC):
  • Bloom syndrome
    Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Myriad Women’s Health, Labcorp Genetics (formerly Invitae), G2P, Laboratory for Molecular Medicine, Orphanet, Genomics England PanelApp, ClinGen
  • osteosarcoma
    Inheritance: AR Classification: MODERATE Submitted by: Genomics England PanelApp
  • breast cancer
    Inheritance: AD Classification: NO_KNOWN Submitted by: Ambry Genetics
  • hereditary nonpolyposis colon cancer
    Inheritance: AD Classification: NO_KNOWN Submitted by: Ambry Genetics

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -11 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.59).
BP6
Variant 15-90784967-C-T is Benign according to our data. Variant chr15-90784967-C-T is described in ClinVar as [Likely_benign]. Clinvar id is 524842.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BP7
Synonymous conserved (PhyloP=-0.203 with no splicing effect.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
BLMNM_000057.4 linkc.2709C>T p.Thr903Thr synonymous_variant Exon 14 of 22 ENST00000355112.8 NP_000048.1 P54132

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
BLMENST00000355112.8 linkc.2709C>T p.Thr903Thr synonymous_variant Exon 14 of 22 1 NM_000057.4 ENSP00000347232.3 P54132

Frequencies

GnomAD3 genomes
Cov.:
31
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461872
Hom.:
0
Cov.:
31
AF XY:
0.00000138
AC XY:
1
AN XY:
727238
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39696
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53414
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
8.99e-7
AC:
1
AN:
1112002
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
⚠️ 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.:
31

ClinVar

Significance: Likely benign
Submissions summary: Benign:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Hereditary cancer-predisposing syndrome Benign:2
Feb 02, 2022
Sema4, Sema4
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:curation

- -

Sep 23, 2020
Ambry Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Bloom syndrome Benign:1
Feb 12, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.59
CADD
Benign
0.71
DANN
Benign
0.52
PhyloP100
-0.20
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.8
Mutation Taster
=100/0
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.0
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs1555422522; hg19: chr15-91328197; API