rs28385142

Positions:

chr15-90804245-G-A

Variant summary

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

The NM_000057.4(BLM):c.3637G>A(p.Glu1213Lys) variant causes a missense change. The variant allele was found at a frequency of 0.00000991 in 1,614,066 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 Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000096 ( 0 hom. )

Consequence

BLM
NM_000057.4 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:5B:1O:1

Conservation

PhyloP100: 5.17

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:

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=0.24683964).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BLM	NM_000057.4 linkuse as main transcript	c.3637G>A	p.Glu1213Lys	missense_variant	19/22	ENST00000355112.8	NP_000048.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BLM	ENST00000355112.8 linkuse as main transcript	c.3637G>A	p.Glu1213Lys	missense_variant	19/22	1	NM_000057.4	ENSP00000347232	P2

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152218

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

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:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000159

AC:

AN:

251392

Hom.:

AF XY:

0.0000221

AC XY:

AN XY:

135862

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.000116

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:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000958

AC:

AN:

1461848

Hom.:

Cov.:

AF XY:

0.00000963

AC XY:

AN XY:

727236

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.000157

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:

0.00000630

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152218

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74370

show subpopulations

Gnomad4 AFR

AF:

0.0000241

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:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000302

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:5Benign:1Other:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Uncertain:3

Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Dec 13, 2023	Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Identified in healthy individuals undergoing whole genome sequencing (PMID: 24728327); Published functional studies demonstrate no damaging effect to growth in the presence of a DNA-damaging agent (PMID: 23129629); This variant is associated with the following publications: (PMID: 24728327, 23129629) -
Uncertain significance, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Apr 28, 2017	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Jan 17, 2023	The frequency of this variant in the general population, 0.00011 (4/35436 chromosomes, http://gnomad.broadinstitute.org), is uninformative in assessment of its pathogenicity. In the published literature, the variant has been reported in unaffected individuals (PMID: 24728327 (2014)). A yeast based functional study has shown that this variant does not display sensitivity to a DNA damaging agent (PMID: 23129629 (2012)). However, additional studies are needed to determine the global effect of this variant on BLM protein function. Analysis of this variant using bioinformatics tools for the prediction of the effect of amino acid changes on protein structure and function yielded predictions that this variant is benign. Based on the available information, we are unable to determine the clinical significance of this variant. -

Bloom syndrome

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Baylor Genetics	Feb 23, 2020	This variant was determined to be of uncertain significance according to ACMG Guidelines, 2015 [PMID:25741868]. -
Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Sep 26, 2022	This sequence change replaces glutamic acid, which is acidic and polar, with lysine, which is basic and polar, at codon 1213 of the BLM protein (p.Glu1213Lys). This variant is present in population databases (rs28385142, gnomAD 0.01%). 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: 133702). 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. Experimental studies have shown that this missense change does not substantially affect BLM function (PMID: 23129629). 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 submitter

clinical testing

Ambry Genetics

Oct 11, 2019

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. -

not specified

Other:1

not provided, no classification provided

reference population

ITMI

Sep 19, 2013

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.14

BayesDel_addAF

Benign

-0.029

BayesDel_noAF

Uncertain

-0.050

CADD

Uncertain

DANN

Pathogenic

1.0

DEOGEN2

Benign

0.33

Eigen

Uncertain

0.23

Eigen_PC

Uncertain

0.40

FATHMM_MKL

Uncertain

0.95

LIST_S2

Uncertain

0.94

M_CAP

Benign

0.015

MetaRNN

Benign

0.25

MetaSVM

Benign

-0.93

MutationAssessor

Uncertain

2.1

MutationTaster

Benign

1.0

D;D

PrimateAI

Uncertain

0.51

PROVEAN

Uncertain

-3.4

REVEL

Benign

0.18

Sift

Uncertain

0.013

Sift4G

Uncertain

0.011

Polyphen

0.066

Vest4

0.40

MutPred

0.25

Gain of MoRF binding (P = 0.0037);

MVP

0.78

MPC

0.12

ClinPred

0.60

GERP RS

5.9

Varity_R

0.54

gMVP

0.52

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.

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