15-90811306-T-C

Variant names:

• chr15-90811306-T-C
• rs1222912167
• NM_000057.4:c.3976T>C

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_000057.4(BLM):​c.3976T>C​(p.Phe1326Leu) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,886 control chromosomes in the GnomAD database, with no homozygous occurrence. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. F1326I) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: BLM NM_000057.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 4.87
• Publications: 0 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

ENSG00000287061 (HGNC:):

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

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.3976T>C	p.Phe1326Leu	missense	Exon 21 of 22	NP_000048.1
	BLM	NM_001287246.2		c.3976T>C	p.Phe1326Leu	missense	Exon 22 of 23	NP_001274175.1
	BLM	NM_001287247.2		c.3583T>C	p.Phe1195Leu	missense	Exon 19 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.3976T>C	p.Phe1326Leu	missense	Exon 21 of 22	ENSP00000347232.3
	BLM	ENST00000560509.5	TSL:1	c.3583T>C	p.Phe1195Leu	missense	Exon 19 of 20	ENSP00000454158.1
	BLM	ENST00000559724.5	TSL:1	n.*2900T>C		non_coding_transcript_exon	Exon 21 of 22	ENSP00000453359.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461886 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 727244

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.0000252 AC: 1 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53416

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1112008

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.93
BayesDel_addAF	Pathogenic	0.16	D
BayesDel_noAF	Uncertain	0.0
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.54	D
Eigen	Uncertain	0.66
Eigen_PC	Uncertain	0.61
FATHMM_MKL	Uncertain	0.95	D
LIST_S2	Benign	0.78	T
M_CAP	Benign	0.065	D
MetaRNN	Uncertain	0.66	D
MetaSVM	Benign	-0.68	T
MutationAssessor	Uncertain	2.5	M
PhyloP100		4.9
PrimateAI	Uncertain	0.56	T
PROVEAN	Uncertain	-3.1	D
REVEL	Benign	0.27
Sift	Uncertain	0.0020	D
Sift4G	Benign	0.092	T
Polyphen		1.0	D
Vest4		0.60
MutPred		0.35		Gain of MoRF binding (P = 0.1268)
MVP		0.88
MPC		0.12
ClinPred		0.93	D
GERP RS		5.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.60
gMVP		0.52

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

Other links and lift over

dbSNP: rs1222912167; hg19: chr15-91354536;