13-30462666-CT-C

Position:

• chr13-30462666-CT-C

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PVS1_Strong PM2

The NM_002128.7(HMGB1):​c.342delA​(p.Gly115fs) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: HMGB1 NM_002128.7 frameshift
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.20

Genes affected

HMGB1 (HGNC:4983): (high mobility group box 1) This gene encodes a protein that belongs to the High Mobility Group-box superfamily. The encoded non-histone, nuclear DNA-binding protein regulates transcription, and is involved in organization of DNA. This protein plays a role in several cellular processes, including inflammation, cell differentiation and tumor cell migration. Multiple pseudogenes of this gene have been identified. Alternative splicing results in multiple transcript variants that encode the same protein. [provided by RefSeq, Sep 2015]

HMGB1 (HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most 50 bp of the penultimate exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.472 CDS is truncated, and there are 0 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
HMGB1	NM_002128.7	c.342delA	p.Gly115fs	frameshift_variant	4/5	ENST00000341423.10	NP_002119.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
HMGB1	ENST00000341423.10	c.342delA	p.Gly115fs	frameshift_variant	4/5	1	NM_002128.7	ENSP00000345347.5

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Neurodevelopmental disorder Uncertain:1

Uncertain significance, criteria provided, single submitter

curation

Broad Center for Mendelian Genomics, Broad Institute of MIT and Harvard

Nov 21, 2024

The heterozygous p.Gly115GlufsTer37 variant in HMGB1 was identified by our study in 1 individual with a neurodevelopmental disorder. While this gene is still lacking sufficient evidence to establish a gene-disease relationship, we believe this is a possible novel gene candidate for neurodevelopmental disorders. Given the limited information about this gene-disease relationship, the significance of the p.Gly115GlufsTer37 variant is uncertain. If you have any additional information about functional evidence or other individuals with this phenotype that also have variants in HMGB1 we encourage you to reach out to us. -

Computational scores

Source: dbNSFP v4.3

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr13-31036803;