rs776516663

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2BP4

The NM_000057.4(BLM):​c.1211G>A​(p.Arg404Gln) variant causes a missense change. The variant allele was found at a frequency of 0.0000136 in 1,613,794 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 Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000014 ( 0 hom. )

Consequence

BLM
NM_000057.4 missense

Scores

3
7
9

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 5.69
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 Uncertain_significance. Variant got 1 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.40132672).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
BLMNM_000057.4 linkuse as main transcriptc.1211G>A p.Arg404Gln missense_variant 6/22 ENST00000355112.8 NP_000048.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
BLMENST00000355112.8 linkuse as main transcriptc.1211G>A p.Arg404Gln missense_variant 6/221 NM_000057.4 ENSP00000347232 P2

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
152012
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
GnomAD3 exomes
AF:
0.0000278
AC:
7
AN:
251384
Hom.:
0
AF XY:
0.0000147
AC XY:
2
AN XY:
135870
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000217
Gnomad SAS exome
AF:
0.0000327
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000144
AC:
21
AN:
1461782
Hom.:
0
Cov.:
33
AF XY:
0.0000110
AC XY:
8
AN XY:
727204
show subpopulations
Gnomad4 AFR exome
AF:
0.0000597
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.000151
Gnomad4 SAS exome
AF:
0.0000116
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000989
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.00000658
AC:
1
AN:
152012
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74234
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.0000113
ExAC
AF:
0.0000247
AC:
3
EpiCase
AF:
0.000109
EpiControl
AF:
0.0000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Bloom syndrome Uncertain:2
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 24, 2024This sequence change replaces arginine, which is basic and polar, with glutamine, which is neutral and polar, at codon 404 of the BLM protein (p.Arg404Gln). This variant is present in population databases (rs776516663, gnomAD 0.02%). 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: 454069). 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. -
Uncertain significance, no assertion criteria providedclinical testingNatera, Inc.Aug 31, 2020- -
Hereditary cancer-predisposing syndrome Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingAmbry GeneticsMar 20, 2023The p.R404Q variant (also known as c.1211G>A), located in coding exon 5 of the BLM gene, results from a G to A substitution at nucleotide position 1211. The arginine at codon 404 is replaced by glutamine, an amino acid with highly similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.24
BayesDel_addAF
Benign
-0.090
T
BayesDel_noAF
Uncertain
-0.070
CADD
Uncertain
25
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.43
T;.
Eigen
Uncertain
0.66
Eigen_PC
Pathogenic
0.69
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Benign
0.84
T;T
M_CAP
Benign
0.048
D
MetaRNN
Benign
0.40
T;T
MetaSVM
Benign
-0.37
T
MutationAssessor
Uncertain
2.1
M;.
MutationTaster
Benign
1.0
D;D
PrimateAI
Benign
0.34
T
PROVEAN
Benign
-2.2
N;N
REVEL
Uncertain
0.29
Sift
Uncertain
0.024
D;D
Sift4G
Uncertain
0.028
D;D
Polyphen
0.98
D;.
Vest4
0.44
MutPred
0.65
Gain of ubiquitination at K409 (P = 0.0584);Gain of ubiquitination at K409 (P = 0.0584);
MVP
0.85
MPC
0.27
ClinPred
0.34
T
GERP RS
6.0
Varity_R
0.51
gMVP
0.52

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.14
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: rs776516663; hg19: chr15-91303500; COSMIC: COSV105827074; COSMIC: COSV105827074; API