15-90794254-G-T

Position:

• chr15-90794254-G-T

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM1 PM2 PP3_Strong PP5

The NM_000057.4(BLM):​c.3107G>T​(p.Cys1036Phe) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. C1036S) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: BLM NM_000057.4 missense
• Clinical Significance: Pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 9.73

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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

• PM1: In a binding_site (size 0) in uniprot entity BLM_HUMAN
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.986
• PP5: Variant 15-90794254-G-T is Pathogenic according to our data. Variant chr15-90794254-G-T is described in ClinVar as [Pathogenic]. Clinvar id is 5457.Status of the report is no_assertion_criteria_provided, 0 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
BLM	NM_000057.4	c.3107G>T	p.Cys1036Phe	missense_variant	16/22	ENST00000355112.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
BLM	ENST00000355112.8	c.3107G>T	p.Cys1036Phe	missense_variant	16/22	1	NM_000057.4	P2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: no assertion criteria provided

Submissions by phenotype

Bloom syndrome Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Sep 01, 1997

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.44	D
BayesDel_noAF	Pathogenic	0.39
CADD	Pathogenic	29
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.72	D;.
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	1.0
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.98	D;D
M_CAP	Uncertain	0.21	D
MetaRNN	Pathogenic	0.99	D;D
MetaSVM	Uncertain	0.79	D
MutationAssessor	Pathogenic	4.6	H;.
MutationTaster	Benign	1.0	A;A
PrimateAI	Uncertain	0.73	T
PROVEAN	Pathogenic	-11	D;D
REVEL	Pathogenic	0.85
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	D;.
Vest4		0.96
MutPred		0.96		Gain of helix (P = 0.132);Gain of helix (P = 0.132);
MVP		0.99
MPC		0.59
ClinPred		1.0	D
GERP RS		5.5
Varity_R		1.0
gMVP		0.89

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

Other links and lift over

dbSNP: rs137853153; hg19: chr15-91337484;