rs770017301

Variant names:

• chr15-90749382-A-G
• rs770017301
• NM_000057.4:c.114A>G

Variant summary

Our verdict is Benign. The variant received -13 ACMG points: 0P and 13B. BP4_Strong BP6_Very_Strong BP7

The NM_000057.4(BLM):​c.114A>G​(p.Lys38Lys) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000449 in 1,604,044 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 Likely benign (★★).

• Frequency:
  • Genomes: 𝑓 0.000059 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000043 (0 hom.)
• Consequence: BLM NM_000057.4 synonymous
• Clinical Significance: Benign/Likely benign criteria provided, multiple submitters, no conflicts B:5
• Conservation: PhyloP100: 1.33
• 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: 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

ACMG classification

Our verdict: Benign. The variant received -13 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.55).
• BP6: Variant 15-90749382-A-G is Benign according to our data. Variant chr15-90749382-A-G is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 454066.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BP7: Synonymous conserved (PhyloP=1.33 with no splicing effect.

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

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	BLM	NM_000057.4	MANE Select	c.114A>G	p.Lys38Lys	synonymous	Exon 3 of 22	NP_000048.1
	BLM	NM_001287246.2		c.114A>G	p.Lys38Lys	synonymous	Exon 4 of 23	NP_001274175.1
	BLM	NM_001287247.2		c.114A>G	p.Lys38Lys	synonymous	Exon 3 of 20	NP_001274176.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	BLM	ENST00000355112.8	TSL:1 MANE Select	c.114A>G	p.Lys38Lys	synonymous	Exon 3 of 22	ENSP00000347232.3
	BLM	ENST00000560509.5	TSL:1	c.114A>G	p.Lys38Lys	synonymous	Exon 3 of 20	ENSP00000454158.1
	BLM	ENST00000559724.5	TSL:1	n.114A>G		non_coding_transcript_exon	Exon 3 of 22	ENSP00000453359.1

Frequencies

GnomAD3 genomes AF: 0.0000591 AC: 9 AN: 152220 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000131

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: 0.0000735

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.0000564 AC: 14 AN: 248404 AF XY: 0.0000593

Gnomad AFR exome AF: 0.0000645

Gnomad AMR exome AF: 0.0000880

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000888

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000434 AC: 63 AN: 1451824 Hom.: 0 Cov.: 30 AF XY: 0.0000360 AC XY: 26 AN XY: 722674

African (AFR) AF: 0.0000604 AC: 2 AN: 33096

American (AMR) AF: 0.000136 AC: 6 AN: 44248

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26012

East Asian (EAS) AF: 0.00 AC: 0 AN: 39618

South Asian (SAS) AF: 0.00 AC: 0 AN: 85610

European-Finnish (FIN) AF: 0.0000187 AC: 1 AN: 53362

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5734

European-Non Finnish (NFE) AF: 0.0000444 AC: 49 AN: 1104138

Other (OTH) AF: 0.0000833 AC: 5 AN: 60006

GnomAD4 genome AF: 0.0000591 AC: 9 AN: 152220 Hom.: 0 Cov.: 32 AF XY: 0.0000403 AC XY: 3 AN XY: 74368

African (AFR) AF: 0.0000241 AC: 1 AN: 41452

American (AMR) AF: 0.000131 AC: 2 AN: 15288

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5200

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

European-Finnish (FIN) AF: 0.0000942 AC: 1 AN: 10618

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

European-Non Finnish (NFE) AF: 0.0000735 AC: 5 AN: 68042

Other (OTH) AF: 0.00 AC: 0 AN: 2092

Alfa AF: 0.0000868 Hom.: 0

Bravo AF: 0.0000604

ClinVar

ClinVar submissions as Germline

Significance: Benign/Likely benign

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	-	3	Bloom syndrome (3)
-	-	1	BLM-related disorder (1)
-	-	1	Hereditary cancer-predisposing syndrome (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.55
CADD	Benign	7.6
DANN	Benign	0.62
PhyloP100		1.3
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Mutation Taster		=99/1	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.050		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs770017301; hg19: chr15-91292612;