2-25234346-CG-C

Variant names:

• chr2-25234346-CG-C
• rs762357545
• NM_022552.5:c.2671delC

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PVS1_Moderate PM2 PP5_Moderate

The NM_022552.5(DNMT3A):​c.2671delC​(p.Arg891GlyfsTer15) 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 Pathogenic (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: DNMT3A NM_022552.5 frameshift
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 2.49

Genes affected

DNMT3A (HGNC:2978): (DNA methyltransferase 3 alpha) CpG methylation is an epigenetic modification that is important for embryonic development, imprinting, and X-chromosome inactivation. Studies in mice have demonstrated that DNA methylation is required for mammalian development. This gene encodes a DNA methyltransferase that is thought to function in de novo methylation, rather than maintenance methylation. The protein localizes to the cytoplasm and nucleus and its expression is developmentally regulated. [provided by RefSeq, Mar 2016]

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 exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.0248 CDS is truncated, and there are 2 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 2-25234346-CG-C is Pathogenic according to our data. Variant chr2-25234346-CG-C is described in ClinVar as [Pathogenic]. Clinvar id is 3679851.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
DNMT3A	NM_022552.5	c.2671delC	p.Arg891GlyfsTer15	frameshift_variant	Exon 23 of 23	ENST00000321117.10	NP_072046.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
DNMT3A	ENST00000321117.10	c.2671delC	p.Arg891GlyfsTer15	frameshift_variant	Exon 23 of 23	1	NM_022552.5	ENSP00000324375.5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1461798 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727188

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: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Tatton-Brown-Rahman overgrowth syndrome Pathogenic:1

May 31, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Arg891Glyfs*15) in the DNMT3A gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 22 amino acid(s) of the DNMT3A protein. This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with DNMT3A-related conditions. This variant disrupts a region of the DNMT3A protein in which other variant(s) (p.Pro904Leu) have been determined to be pathogenic (PMID: 24614070, 31961069). This suggests that this is a clinically significant region of the protein, and that variants that disrupt it are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

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

LitVar

Other links and lift over

dbSNP: rs762357545; hg19: chr2-25457215;