chr15-90747496-T-G

Variant names:

• chr15-90747496-T-G
• rs886051550
• NM_000057.4:c.98+6T>G

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 1P and 0B. PP3

The NM_000057.4(BLM):​c.98+6T>G variant causes a splice region, intron change. The variant allele was found at a frequency of 0.000014 in 1,573,828 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 predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 31)
  • Exomes 𝑓: 0.000015 (0 hom.)
• Consequence: BLM NM_000057.4 splice_region, intron
• Scores: Splicing: ADA: 0.9963
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:5
• Conservation: PhyloP100: 4.14
• Publications: 1 publications found

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: Orphanet, Labcorp Genetics (formerly Invitae), G2P, Myriad Women’s Health, Genomics England PanelApp, ClinGen, Laboratory for Molecular Medicine
• osteosarcoma

  Inheritance: AR Classification: MODERATE Submitted by: Genomics England PanelApp
• colorectal cancer

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen
• breast cancer

  Inheritance: AD Classification: NO_KNOWN Submitted by: Ambry Genetics
• hereditary nonpolyposis colon cancer

  Inheritance: AD Classification: NO_KNOWN Submitted by: Ambry Genetics

ACMG classification

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000057.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	BLM	NM_000057.4	MANE Select	c.98+6T>G		splice_region intron	N/A	NP_000048.1	P54132
	BLM	NM_001287246.2		c.98+6T>G		splice_region intron	N/A	NP_001274175.1	P54132
	BLM	NM_001287247.2		c.98+6T>G		splice_region intron	N/A	NP_001274176.1	H0YNU5

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	BLM	ENST00000355112.8	TSL:1 MANE Select	c.98+6T>G		splice_region intron	N/A	ENSP00000347232.3	P54132
	BLM	ENST00000560509.5	TSL:1	c.98+6T>G		splice_region intron	N/A	ENSP00000454158.1	H0YNU5
	BLM	ENST00000559724.5	TSL:1	n.98+6T>G		splice_region intron	N/A	ENSP00000453359.1	H0YLV8

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152120 Hom.: 0 Cov.: 31

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: 0.00000888 AC: 2 AN: 225240 AF XY: 0.00000825

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: 0.0000207

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000148 AC: 21 AN: 1421708 Hom.: 0 Cov.: 28 AF XY: 0.00000990 AC XY: 7 AN XY: 707360

African (AFR) AF: 0.00 AC: 0 AN: 32608

American (AMR) AF: 0.00 AC: 0 AN: 43490

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25544

East Asian (EAS) AF: 0.00 AC: 0 AN: 39270

South Asian (SAS) AF: 0.00 AC: 0 AN: 83908

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52378

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5152

European-Non Finnish (NFE) AF: 0.0000167 AC: 18 AN: 1080572

Other (OTH) AF: 0.0000510 AC: 3 AN: 58786

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152120 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 74306

African (AFR) AF: 0.00 AC: 0 AN: 41414

American (AMR) AF: 0.00 AC: 0 AN: 15272

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5190

South Asian (SAS) AF: 0.00 AC: 0 AN: 4830

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10608

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68018

Other (OTH) AF: 0.00 AC: 0 AN: 2088

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000756

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	3	-	Bloom syndrome (3)
-	2	-	Hereditary cancer-predisposing syndrome (2)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.35
CADD	Benign	12
DANN	Benign	0.93
PhyloP100		4.1
Mutation Taster		=43/57	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.77
SpliceAI score (max)		0.92		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.92		Position offset: -6

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

Other links and lift over

dbSNP: rs886051550; hg19: chr15-91290726;