15-44711547-A-G

Position:

• chr15-44711547-A-G

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PVS1 PM2

The NM_004048.4(B2M):​c.1A>G​(p.Met1?) variant causes a start lost change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,546 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as other (no stars).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: B2M NM_004048.4 start_lost
• Clinical Significance: - - O:1
• Conservation: PhyloP100: 2.09

Genes affected

B2M (HGNC:914): (beta-2-microglobulin) This gene encodes a serum protein found in association with the major histocompatibility complex (MHC) class I heavy chain on the surface of nearly all nucleated cells. The protein has a predominantly beta-pleated sheet structure that can form amyloid fibrils in some pathological conditions. The encoded antimicrobial protein displays antibacterial activity in amniotic fluid. A mutation in this gene has been shown to result in hypercatabolic hypoproteinemia.[provided by RefSeq, Aug 2014]

ACMG classification

Verdict is Pathogenic. Variant got 10 ACMG points.

• PVS1: Start lost variant, no new inframe start found.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
B2M	NM_004048.4	c.1A>G	p.Met1?	start_lost	Exon 1 of 4	ENST00000648006.3	NP_004039.1
B2M	XM_005254549.4	c.1A>G	p.Met1?	start_lost	Exon 1 of 2		XP_005254606.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
B2M	ENST00000648006.3	c.1A>G	p.Met1?	start_lost	Exon 1 of 4		NM_004048.4	ENSP00000497910.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461546 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727096

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 32

ClinVar

Significance: -

Submissions summary: Other:1

Revision: -

Submissions by phenotype

Neoplasm Other:1

-, criteria provided, single submitter

clinical testing

Center for Genomic Medicine, Rigshospitalet, Copenhagen University Hospital

Mar 04, 2025

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.20	D
BayesDel_noAF	Uncertain	0.050
CADD	Benign	21
DANN	Uncertain	0.98
DEOGEN2	Benign	0.072	T;D;D;D
Eigen	Benign	0.052
Eigen_PC	Benign	0.032
FATHMM_MKL	Uncertain	0.87	D
M_CAP	Pathogenic	0.41	D
MetaRNN	Pathogenic	0.98	D;D;D;D
MetaSVM	Benign	-0.76	T
PROVEAN	Benign	-2.0	N;N;N;.
REVEL	Benign	0.29
Sift	Pathogenic	0.0	D;D;D;.
Sift4G	Pathogenic	0.0	D;D;D;.
Polyphen		0.86	P;P;P;P
Vest4		0.74
MutPred		0.91		Loss of catalytic residue at M1 (P = 0.1006);Loss of catalytic residue at M1 (P = 0.1006);Loss of catalytic residue at M1 (P = 0.1006);Loss of catalytic residue at M1 (P = 0.1006);
MVP		0.92
ClinPred		0.90	D
GERP RS		5.3
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.95
gMVP		0.59

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs1023835002; hg19: chr15-45003745; COSMIC: COSV62562870; COSMIC: COSV62562870;