rs149598003

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2BP4_StrongBP6

The NM_000057.4(BLM):ā€‹c.847A>Gā€‹(p.Thr283Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000986 in 1,612,738 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: š‘“ 0.000053 ( 0 hom., cov: 32)
Exomes š‘“: 0.00010 ( 0 hom. )

Consequence

BLM
NM_000057.4 missense

Scores

19

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3B:1O:1

Conservation

PhyloP100: -2.63
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]

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ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -3 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.04011315).
BP6
Variant 15-90751834-A-G is Benign according to our data. Variant chr15-90751834-A-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 133711.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=1, Uncertain_significance=2, not_provided=1}.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
BLMNM_000057.4 linkuse as main transcriptc.847A>G p.Thr283Ala missense_variant 4/22 ENST00000355112.8 NP_000048.1 P54132

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
BLMENST00000355112.8 linkuse as main transcriptc.847A>G p.Thr283Ala missense_variant 4/221 NM_000057.4 ENSP00000347232.3 P54132

Frequencies

GnomAD3 genomes
AF:
0.0000525
AC:
8
AN:
152274
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
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:
0.000103
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000318
AC:
8
AN:
251236
Hom.:
0
AF XY:
0.0000368
AC XY:
5
AN XY:
135812
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 SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000616
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.000103
AC:
151
AN:
1460464
Hom.:
0
Cov.:
30
AF XY:
0.0000895
AC XY:
65
AN XY:
726630
show subpopulations
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:
0.0000187
Gnomad4 NFE exome
AF:
0.000122
Gnomad4 OTH exome
AF:
0.000249
GnomAD4 genome
AF:
0.0000525
AC:
8
AN:
152274
Hom.:
0
Cov.:
32
AF XY:
0.0000538
AC XY:
4
AN XY:
74402
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.0000654
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.000103
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000828
Hom.:
0
Bravo
AF:
0.0000642
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000494
AC:
6
EpiCase
AF:
0.000109
EpiControl
AF:
0.00

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:3Benign:1Other:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Bloom syndrome Uncertain:3
Uncertain significance, criteria provided, single submitterclinical testingIllumina Laboratory Services, IlluminaApr 27, 2017This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -
Uncertain significance, no assertion criteria providedclinical testingNatera, Inc.May 24, 2018- -
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 29, 2024This sequence change replaces threonine, which is neutral and polar, with alanine, which is neutral and non-polar, at codon 283 of the BLM protein (p.Thr283Ala). This variant is present in population databases (rs149598003, gnomAD 0.006%). 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: 133711). 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%. RNA analysis performed to evaluate the impact of this missense change on mRNA splicing indicates it does not significantly alter splicing (Invitae). 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
Likely benign, criteria provided, single submitterclinical testingAmbry GeneticsJan 05, 2024This 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. -
not specified Other:1
not provided, no classification providedreference populationITMISep 19, 2013- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.064
BayesDel_addAF
Benign
-0.48
T
BayesDel_noAF
Benign
-0.75
CADD
Benign
0.0010
DANN
Benign
0.73
DEOGEN2
Benign
0.051
T;.
Eigen
Benign
-1.7
Eigen_PC
Benign
-1.7
FATHMM_MKL
Benign
0.00078
N
LIST_S2
Benign
0.39
T;T
M_CAP
Benign
0.0059
T
MetaRNN
Benign
0.040
T;T
MetaSVM
Benign
-1.1
T
MutationAssessor
Benign
0.69
N;.
PrimateAI
Benign
0.25
T
PROVEAN
Benign
-0.64
N;N
REVEL
Benign
0.059
Sift
Benign
0.92
T;T
Sift4G
Benign
0.94
T;T
Polyphen
0.0
B;.
Vest4
0.056
MVP
0.55
MPC
0.087
ClinPred
0.033
T
GERP RS
-12
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.017
gMVP
0.068

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs149598003; hg19: chr15-91295064; API