rs201220226

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2BP4_ModerateBP6BP7

The NM_000057.4(BLM):ā€‹c.2898C>Gā€‹(p.Leu966=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000589 in 1,614,004 control chromosomes in the GnomAD database, including 1 homozygotes. 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: š‘“ 0.000059 ( 1 hom., cov: 32)
Exomes š‘“: 0.000059 ( 0 hom. )

Consequence

BLM
NM_000057.4 synonymous

Scores

2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:8

Conservation

PhyloP100: 0.972
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.39).
BP6
Variant 15-90790723-C-G is Benign according to our data. Variant chr15-90790723-C-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 413298.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=5, Benign=2, Uncertain_significance=1}. Variant chr15-90790723-C-G is described in Lovd as [Likely_benign].
BP7
Synonymous conserved (PhyloP=0.972 with no splicing effect.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
BLMNM_000057.4 linkuse as main transcriptc.2898C>G p.Leu966= synonymous_variant 15/22 ENST00000355112.8 NP_000048.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
BLMENST00000355112.8 linkuse as main transcriptc.2898C>G p.Leu966= synonymous_variant 15/221 NM_000057.4 ENSP00000347232 P2

Frequencies

GnomAD3 genomes
AF:
0.0000591
AC:
9
AN:
152164
Hom.:
1
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000965
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:
0.00316
Gnomad NFE
AF:
0.0000588
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000597
AC:
15
AN:
251434
Hom.:
1
AF XY:
0.0000810
AC XY:
11
AN XY:
135884
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000867
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.0000327
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000703
Gnomad OTH exome
AF:
0.000489
GnomAD4 exome
AF:
0.0000588
AC:
86
AN:
1461840
Hom.:
0
Cov.:
31
AF XY:
0.0000646
AC XY:
47
AN XY:
727222
show subpopulations
Gnomad4 AFR exome
AF:
0.000209
Gnomad4 AMR exome
AF:
0.000134
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.0000348
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000396
Gnomad4 OTH exome
AF:
0.000215
GnomAD4 genome
AF:
0.0000591
AC:
9
AN:
152164
Hom.:
1
Cov.:
32
AF XY:
0.0000942
AC XY:
7
AN XY:
74328
show subpopulations
Gnomad4 AFR
AF:
0.0000965
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:
0.0000588
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000868
Hom.:
0
Bravo
AF:
0.0000642
EpiCase
AF:
0.000164
EpiControl
AF:
0.000119

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:1Benign:8
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Bloom syndrome Uncertain:1Benign:5
Likely benign, criteria provided, single submitterclinical testingMendelicsMay 28, 2019- -
Likely benign, no assertion criteria providedclinical testingNatera, Inc.Jul 21, 2018- -
Uncertain significance, criteria provided, single submitterclinical testingIllumina Laboratory Services, IlluminaJan 13, 2018This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -
Benign, criteria provided, single submitterclinical testingKCCC/NGS Laboratory, Kuwait Cancer Control CenterJul 07, 2023- -
Benign, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 30, 2024- -
Likely benign, criteria provided, single submitterclinical testingPars Genome LabMay 18, 2021- -
Hereditary cancer-predisposing syndrome Benign:2
Likely benign, criteria provided, single submittercurationSema4, Sema4Nov 23, 2021- -
Likely benign, criteria provided, single submitterclinical testingAmbry GeneticsMar 14, 2017This 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 provided Benign:1
Likely benign, criteria provided, single submitterclinical testingCeGaT Center for Human Genetics TuebingenMar 01, 2023BLM: BP4, BP7 -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.39
CADD
Benign
4.6
DANN
Benign
0.70

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: rs201220226; hg19: chr15-91333953; COSMIC: COSV61923375; COSMIC: COSV61923375; API