rs1555691311

chr19-10154294-T-C

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM2 PP2 PP3_Strong

The NM_001130823.3(DNMT1):c.2018A>G(p.Glu673Gly) variant causes a missense, splice region 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. 14/25 in silico tools predict a damaging outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: DNMT1 NM_001130823.3 missense, splice_region
• Scores: Splicing: ADA: 0.9999
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.96

Genes affected

DNMT1 (HGNC:2976): (DNA methyltransferase 1) This gene encodes an enzyme that transfers methyl groups to cytosine nucleotides of genomic DNA. This protein is the major enzyme responsible for maintaining methylation patterns following DNA replication and shows a preference for hemi-methylated DNA. Methylation of DNA is an important component of mammalian epigenetic gene regulation. Aberrant methylation patterns are found in human tumors and associated with developmental abnormalities. Variation in this gene has been associated with cerebellar ataxia, deafness, and narcolepsy, and neuropathy, hereditary sensory, type IE. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jan 2016]

ACMG classification

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant where missense usually causes diseases, DNMT1
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. Scorers claiming Uncertain: max_spliceai. No scorers claiming Benign.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
DNMT1	NM_001130823.3	c.2018A>G	p.Glu673Gly	missense_variant, splice_region_variant	22/41	ENST00000359526.9
DNMT1	NM_001318730.2	c.1970A>G	p.Glu657Gly	missense_variant, splice_region_variant	21/40
DNMT1	NM_001379.4	c.1970A>G	p.Glu657Gly	missense_variant, splice_region_variant	21/40
DNMT1	NM_001318731.2	c.1655A>G	p.Glu552Gly	missense_variant, splice_region_variant	22/41

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
DNMT1	ENST00000359526.9	c.2018A>G	p.Glu673Gly	missense_variant, splice_region_variant	22/41	1	NM_001130823.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hereditary sensory neuropathy-deafness-dementia syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Sep 15, 2020

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site, but this prediction has not been confirmed by published transcriptional studies. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). This variant is not present in population databases (ExAC no frequency). This sequence change replaces glutamic acid with glycine at codon 673 of the DNMT1 protein (p.Glu673Gly). The glutamic acid residue is highly conserved and there is a moderate physicochemical difference between glutamic acid and glycine. This variant has not been reported in the literature in individuals with DNMT1-related disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.84
BayesDel_addAF	Pathogenic	0.27	D
BayesDel_noAF	Pathogenic	0.14
Cadd	Pathogenic	34
Dann	Pathogenic	1.0
DEOGEN2	Pathogenic	0.95	D;.
Eigen	Pathogenic	0.79
Eigen_PC	Pathogenic	0.72
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.89	D;D
M_CAP	Pathogenic	0.41	D
MetaRNN	Pathogenic	0.92	D;D
MetaSVM	Benign	-0.53	T
MutationAssessor	Pathogenic	3.3	M;.
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Uncertain	0.70	T
PROVEAN	Pathogenic	-6.1	D;D
REVEL	Uncertain	0.57
Sift	Uncertain	0.0010	D;D
Sift4G	Uncertain	0.0020	D;D
Polyphen		1.0	D;D
Vest4		0.83
MutPred		0.64		Loss of sheet (P = 0.0457);.;
MVP		0.77
MPC		2.4
ClinPred		1.0	D
GERP RS		6.2
Varity_R		0.66
gMVP		0.95

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.99
SpliceAI score (max)		0.36		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.36		Position offset: -13

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs1555691311; hg19: chr19-10264970;