15-90784916-G-C

Variant names:

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 0P and 3B. BP4_ModerateBP6

The NM_000057.4(BLM):c.2663-5G>C variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000372 in 1,612,370 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 31)

Exomes 𝑓: 0.0000034 ( 0 hom. )

Consequence

BLM
NM_000057.4 splice_region, intron

Scores

Splicing: ADA: 0.003024

Clinical Significance

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

Conservation

PhyloP100: 0.755

Publications

0 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

BLM links:

ENSG00000300894 (HGNC:):

ENSG00000300894 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -3 ACMG points.

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.38).

BP6

Variant 15-90784916-G-C is Benign according to our data. Variant chr15-90784916-G-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 1626923.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BLM	NM_000057.4 link	c.2663-5G>C		splice_region_variant, intron_variant	Intron 13 of 21	ENST00000355112.8	NP_000048.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BLM	ENST00000355112.8 link	c.2663-5G>C		splice_region_variant, intron_variant	Intron 13 of 21	1	NM_000057.4	ENSP00000347232.3

Frequencies

GnomAD3 genomes

AF:

0.00000658

AC:

AN:

152006

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

GnomAD2 exomes

AF:

0.00000399

AC:

AN:

250936

AF XY:

0.00

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000881

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000342

AC:

AN:

1460364

Hom.:

Cov.:

AF XY:

0.00000275

AC XY:

AN XY:

726238

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

33460

American (AMR)

AF:

0.00

AC:

AN:

44646

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26110

East Asian (EAS)

AF:

0.00

AC:

AN:

39652

South Asian (SAS)

AF:

0.00

AC:

AN:

86100

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53350

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5764

European-Non Finnish (NFE)

AF:

0.00000450

AC:

AN:

1110936

Other (OTH)

AF:

0.00

AC:

AN:

60346

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.565

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<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:

0.00000658

AC:

AN:

152006

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74246

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

41374

American (AMR)

AF:

0.00

AC:

AN:

15254

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3468

East Asian (EAS)

AF:

0.00

AC:

AN:

5184

South Asian (SAS)

AF:

0.00

AC:

AN:

4822

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10570

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.0000147

AC:

AN:

68016

Other (OTH)

AF:

0.00

AC:

AN:

2090

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.425

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Alfa

AF:

0.00

Hom.:

Bravo

AF:

0.00000378

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1Benign:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Hereditary cancer-predisposing syndrome

Uncertain:1

May 30, 2023

Ambry Genetics

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

The c.2663-5G>C intronic variant results from a G to C substitution 5 nucleotides upstream from coding exon 13 in the BLM gene. This nucleotide position is not well conserved in available vertebrate species. In silico splice site analysis predicts that this alteration will not have any significant effect on splicing. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear.

Bloom syndrome

Benign:1

Mar 06, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance:Likely benign

Review Status:criteria provided, single submitter

Collection Method:clinical testing

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.38

CADD

Benign

(source)

DANN

Benign

0.79

PhyloP100

0.76

Mutation Taster

=97/3

polymorphism

(source)

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Benign

0.0030

dbscSNV1_RF

Benign

0.056

SpliceAI score (max)

0.070

Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

Age Distribution

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over