15-90760863-A-G

Position:

chr15-90760863-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_000057.4(BLM):c.1490A>G(p.Gln497Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000186 in 1,614,010 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 13/21 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: 𝑓 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000020 ( 1 hom. )

Consequence

BLM
NM_000057.4 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:4B:1

Conservation

PhyloP100: 2.71

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 links:

BLM (HGNC:):

BLM links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 0 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.16166195).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BLM	NM_000057.4 linkuse as main transcript	c.1490A>G	p.Gln497Arg	missense_variant	7/22	ENST00000355112.8	NP_000048.1	P54132

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BLM	ENST00000355112.8 linkuse as main transcript	c.1490A>G	p.Gln497Arg	missense_variant	7/22	1	NM_000057.4	ENSP00000347232.3		P54132

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152234

Hom.:

Cov.:

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:

0.0000360

AC:

AN:

250330

Hom.:

AF XY:

0.0000221

AC XY:

AN XY:

135482

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000868

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:

0.0000354

Gnomad OTH exome

AF:

0.000328

GnomAD4 exome

AF:

0.0000198

AC:

AN:

1461776

Hom.:

Cov.:

AF XY:

0.0000234

AC XY:

AN XY:

727184

show subpopulations

Gnomad4 AFR exome

AF:

0.000149

Gnomad4 AMR exome

AF:

0.0000671

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000450

Gnomad4 OTH exome

AF:

0.0000662

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152234

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74384

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

Alfa

AF:

0.0000675

Hom.:

Bravo

AF:

0.0000151

ExAC

AF:

0.0000247

AC:

EpiCase

AF:

0.0000545

EpiControl

AF:

0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:4Benign:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Bloom syndrome

Uncertain:2Benign:1

Uncertain significance, criteria provided, single submitter	clinical testing	Baylor Genetics	Jan 27, 2020	This variant was determined to be of uncertain significance according to ACMG Guidelines, 2015 [PMID:25741868]. -
Benign, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 27, 2024	- -
Uncertain significance, no assertion criteria provided	clinical testing	Natera, Inc.	Dec 17, 2018	- -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Mayo Clinic Laboratories, Mayo Clinic

May 02, 2024

BP4, PM2 -

Hereditary cancer-predisposing syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jan 30, 2023

The p.Q497R variant (also known as c.1490A>G), located in coding exon 6 of the BLM gene, results from an A to G substitution at nucleotide position 1490. The glutamine at codon 497 is replaced by arginine, an amino acid with highly similar properties. This amino acid position is not well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. 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

0.095

BayesDel_addAF

Benign

-0.29

BayesDel_noAF

Benign

-0.45

CADD

Benign

DANN

Uncertain

0.99

DEOGEN2

Benign

0.11

T;.

Eigen

Benign

-0.24

Eigen_PC

Benign

-0.12

FATHMM_MKL

Uncertain

0.86

LIST_S2

Benign

0.48

T;T

M_CAP

Benign

0.013

MetaRNN

Benign

0.16

T;T

MetaSVM

Benign

-1.1

MutationAssessor

Uncertain

2.0

M;.

PrimateAI

Benign

0.31

PROVEAN

Benign

-1.1

N;N

REVEL

Benign

0.020

Sift

Uncertain

0.029

D;D

Sift4G

Benign

0.12

T;T

Polyphen

0.45

P;.

Vest4

0.23

MutPred

0.25

Gain of MoRF binding (P = 0.0191);Gain of MoRF binding (P = 0.0191);

MVP

0.80

MPC

0.10

ClinPred

0.057

GERP RS

3.3

Varity_R

0.11

gMVP

0.55

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.020

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over