chr15-90761025-A-G

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP4_StrongBP6

The NM_000057.4(BLM):​c.1652A>G​(p.Tyr551Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000563 in 1,599,588 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. Y551D) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000055 ( 0 hom. )

Consequence

BLM
NM_000057.4 missense

Scores

19

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:1

Conservation

PhyloP100: -1.13

Publications

2 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: Likely_benign. The variant received -5 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.05049604).
BP6
Variant 15-90761025-A-G is Benign according to our data. Variant chr15-90761025-A-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 405284.We mark this variant Likely_benign, oryginal submission is: [Conflicting_classifications_of_pathogenicity].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
BLMNM_000057.4 linkc.1652A>G p.Tyr551Cys missense_variant Exon 7 of 22 ENST00000355112.8 NP_000048.1 P54132

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
BLMENST00000355112.8 linkc.1652A>G p.Tyr551Cys missense_variant Exon 7 of 22 1 NM_000057.4 ENSP00000347232.3 P54132

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152204
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000126
AC:
3
AN:
238964
AF XY:
0.00000774
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000273
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000553
AC:
8
AN:
1447384
Hom.:
0
Cov.:
31
AF XY:
0.00000417
AC XY:
3
AN XY:
719038
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
32382
American (AMR)
AF:
0.00
AC:
0
AN:
41486
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25522
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39584
South Asian (SAS)
AF:
0.00
AC:
0
AN:
83610
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53064
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5656
European-Non Finnish (NFE)
AF:
0.00000723
AC:
8
AN:
1106388
Other (OTH)
AF:
0.00
AC:
0
AN:
59692
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
1
2
2
3
4
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
AF:
0.00000657
AC:
1
AN:
152204
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74356
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41464
American (AMR)
AF:
0.00
AC:
0
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5194
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68032
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.625
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

Genome 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
Alfa
AF:
0.00
Hom.:
0
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:1Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Bloom syndrome Uncertain:1
Dec 22, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces tyrosine, which is neutral and polar, with cysteine, which is neutral and slightly polar, at codon 551 of the BLM protein (p.Tyr551Cys). This variant is present in population databases (rs746571244, gnomAD 0.003%). This variant has not been reported in the literature in individuals affected with BLM-related conditions. ClinVar contains an entry for this variant (Variation ID: 405284). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt BLM protein function with a negative predictive value of 80%. 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. -

Hereditary cancer-predisposing syndrome Benign:1
Feb 01, 2021
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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.053
BayesDel_addAF
Benign
-0.38
T
BayesDel_noAF
Benign
-0.72
CADD
Benign
0.010
DANN
Benign
0.20
DEOGEN2
Benign
0.10
T;.
Eigen
Benign
-1.8
Eigen_PC
Benign
-1.9
FATHMM_MKL
Benign
0.018
N
LIST_S2
Benign
0.61
T;T
M_CAP
Benign
0.0025
T
MetaRNN
Benign
0.050
T;T
MetaSVM
Benign
-1.1
T
MutationAssessor
Benign
-0.72
N;.
PhyloP100
-1.1
PrimateAI
Benign
0.24
T
PROVEAN
Benign
-1.2
N;N
REVEL
Benign
0.030
Sift
Benign
0.19
T;T
Sift4G
Benign
0.19
T;T
Polyphen
0.0
B;.
Vest4
0.087
MutPred
0.35
Loss of stability (P = 0.0737);Loss of stability (P = 0.0737);
MVP
0.57
MPC
0.11
ClinPred
0.024
T
GERP RS
-10
Varity_R
0.043
gMVP
0.43
Mutation Taster
=92/8
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: rs746571244; hg19: chr15-91304255; COSMIC: COSV61927714; COSMIC: COSV61927714; API