rs35886055

Variant summary

Our verdict is Benign. The variant received -20 ACMG points: 0P and 20B. BP4_StrongBP6_Very_StrongBS1BS2

The NM_000057.4(BLM):​c.419A>G​(p.Glu140Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00169 in 1,614,162 control chromosomes in the GnomAD database, including 56 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 Benign (★★). Synonymous variant affecting the same amino acid position (i.e. E140E) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0088 ( 27 hom., cov: 32)
Exomes 𝑓: 0.00095 ( 29 hom. )

Consequence

BLM
NM_000057.4 missense

Scores

5
13

Clinical Significance

Benign criteria provided, multiple submitters, no conflicts B:10O:1

Conservation

PhyloP100: 3.36

Publications

12 publications found
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 Gene-Disease associations (from GenCC):
  • Bloom syndrome
    Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Myriad Women’s Health, Labcorp Genetics (formerly Invitae), G2P, Laboratory for Molecular Medicine, Orphanet, Genomics England PanelApp, ClinGen
  • osteosarcoma
    Inheritance: AR Classification: MODERATE Submitted by: Genomics England PanelApp
  • breast cancer
    Inheritance: AD Classification: NO_KNOWN Submitted by: Ambry Genetics
  • hereditary nonpolyposis colon cancer
    Inheritance: AD Classification: NO_KNOWN Submitted by: Ambry Genetics

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -20 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.004220754).
BP6
Variant 15-90749687-A-G is Benign according to our data. Variant chr15-90749687-A-G is described in ClinVar as Benign. ClinVar VariationId is 133708.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS1
Variant frequency is greater than expected in population afr. GnomAd4 allele frequency = 0.00883 (1345/152314) while in subpopulation AFR AF = 0.0308 (1282/41562). AF 95% confidence interval is 0.0294. There are 27 homozygotes in GnomAd4. There are 656 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.
BS2
High Homozygotes in GnomAd4 at 27 AR,AD gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
BLMNM_000057.4 linkc.419A>G p.Glu140Gly missense_variant Exon 3 of 22 ENST00000355112.8 NP_000048.1 P54132

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
BLMENST00000355112.8 linkc.419A>G p.Glu140Gly missense_variant Exon 3 of 22 1 NM_000057.4 ENSP00000347232.3 P54132

Frequencies

GnomAD3 genomes
AF:
0.00882
AC:
1342
AN:
152196
Hom.:
27
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0309
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00262
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.0000942
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000147
Gnomad OTH
AF:
0.00573
GnomAD2 exomes
AF:
0.00230
AC:
577
AN:
251314
AF XY:
0.00183
show subpopulations
Gnomad AFR exome
AF:
0.0318
Gnomad AMR exome
AF:
0.00113
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000132
Gnomad OTH exome
AF:
0.000980
GnomAD4 exome
AF:
0.000950
AC:
1389
AN:
1461848
Hom.:
29
Cov.:
31
AF XY:
0.000854
AC XY:
621
AN XY:
727222
show subpopulations
African (AFR)
AF:
0.0346
AC:
1160
AN:
33478
American (AMR)
AF:
0.00148
AC:
66
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39692
South Asian (SAS)
AF:
0.0000580
AC:
5
AN:
86258
European-Finnish (FIN)
AF:
0.0000187
AC:
1
AN:
53404
Middle Eastern (MID)
AF:
0.000173
AC:
1
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000558
AC:
62
AN:
1111998
Other (OTH)
AF:
0.00156
AC:
94
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.483
Heterozygous variant carriers
0
81
162
244
325
406
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
38
76
114
152
190
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00883
AC:
1345
AN:
152314
Hom.:
27
Cov.:
32
AF XY:
0.00881
AC XY:
656
AN XY:
74470
show subpopulations
African (AFR)
AF:
0.0308
AC:
1282
AN:
41562
American (AMR)
AF:
0.00261
AC:
40
AN:
15302
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5180
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.0000942
AC:
1
AN:
10620
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.000147
AC:
10
AN:
68030
Other (OTH)
AF:
0.00567
AC:
12
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
Heterozygous variant carriers
0
62
123
185
246
308
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Genome Hom
Variant carriers
0
20
40
60
80
100
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00333
Hom.:
16
Bravo
AF:
0.00965
ESP6500AA
AF:
0.0330
AC:
145
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.00290
AC:
352
Asia WGS
AF:
0.00318
AC:
11
AN:
3478
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Benign
Submissions summary: Benign:10Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Bloom syndrome Benign:4
Feb 04, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This 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 and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Jul 07, 2023
KCCC/NGS Laboratory, Kuwait Cancer Control Center
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jun 13, 2017
Natera, Inc.
Significance:Benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

not provided Benign:3
-
Breakthrough Genomics, Breakthrough Genomics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:not provided

- -

Aug 31, 2016
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: The BLM c.419A>G (p.Glu140Gly) variant involves the alteration of a conserved nucleotide. 3/4 in silico tools predict a benign outcome for this variant (SNPs&GO not captured due to low reliability index). This variant was found in 351/121252 control chromosomes (2 homozygotes), predominantly observed in the African subpopulation at a frequency of 0.0317352 (327/10304). This frequency is about 9 times the estimated maximal expected allele frequency of a pathogenic BLM variant (0.0035355), suggesting this is likely a benign polymorphism found primarily in the populations of African origin. In addition, multiple clinical diagnostic laboratories/reputable databases classified this variant as benign. The variant of interest has not, to our knowledge, been reported in affected individuals via publications nor evaluated for functional impact by in vivo/vitro studies. Taken together, the variant is classified as benign. -

Sep 15, 2014
Center for Pediatric Genomic Medicine, Children's Mercy Hospital and Clinics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Benign:2Other:1
Jul 09, 2021
Quest Diagnostics Nichols Institute San Juan Capistrano
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Sep 19, 2013
ITMI
Significance:not provided
Review Status:no classification provided
Collection Method:reference population

- -

Oct 25, 2013
GeneDx
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -

Hereditary cancer-predisposing syndrome Benign:1
Sep 29, 2016
Ambry Genetics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.098
BayesDel_addAF
Benign
-0.41
T
BayesDel_noAF
Benign
-0.33
CADD
Benign
20
DANN
Uncertain
1.0
DEOGEN2
Benign
0.085
T;.
Eigen
Uncertain
0.25
Eigen_PC
Uncertain
0.37
FATHMM_MKL
Uncertain
0.93
D
LIST_S2
Benign
0.74
T;T
MetaRNN
Benign
0.0042
T;T
MetaSVM
Benign
-1.0
T
MutationAssessor
Uncertain
2.3
M;.
PhyloP100
3.4
PrimateAI
Benign
0.38
T
PROVEAN
Benign
-1.8
N;N
REVEL
Benign
0.071
Sift
Benign
0.26
T;T
Sift4G
Benign
0.49
T;T
Polyphen
0.68
P;.
Vest4
0.21
MVP
0.82
MPC
0.33
ClinPred
0.024
T
GERP RS
6.0
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.097
gMVP
0.11
Mutation Taster
=89/11
polymorphism

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

Other links and lift over

dbSNP: rs35886055; hg19: chr15-91292917; COSMIC: COSV104665711; API