20-32780380-C-G

Position:

• chr20-32780380-C-G

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 3P and 4B. PM2 PP2 BP4_Strong

The NM_006892.4(DNMT3B):​c.57C>G​(p.Asp19Glu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,760 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. D19D) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: DNMT3B NM_006892.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.00200

Genes affected

DNMT3B (HGNC:2979): (DNA methyltransferase 3 beta) 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 which is thought to function in de novo methylation, rather than maintenance methylation. The protein localizes primarily to the nucleus and its expression is developmentally regulated. Mutations in this gene cause the immunodeficiency-centromeric instability-facial anomalies (ICF) syndrome. Eight alternatively spliced transcript variants have been described. The full length sequences of variants 4 and 5 have not been determined. [provided by RefSeq, May 2011]

ACMG classification

Verdict is Likely_benign. Variant got -1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), DNMT3B. . Gene score misZ 1.5 (greater than the threshold 3.09). Trascript score misZ 3.3234 (greater than threshold 3.09). GenCC has associacion of gene with immunodeficiency-centromeric instability-facial anomalies syndrome, immunodeficiency-centromeric instability-facial anomalies syndrome 1.
• BP4: Computational evidence support a benign effect (MetaRNN=0.061440587).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
DNMT3B	NM_006892.4	c.57C>G	p.Asp19Glu	missense_variant	2/23	ENST00000328111.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
DNMT3B	ENST00000328111.6	c.57C>G	p.Asp19Glu	missense_variant	2/23	1	NM_006892.4	A2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461760 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 727182

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: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Centromeric instability of chromosomes 1,9 and 16 and immunodeficiency Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 24, 2021

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 missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0". The glutamic acid amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. This variant has not been reported in the literature in individuals affected with DNMT3B-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces aspartic acid, which is acidic and polar, with glutamic acid, which is acidic and polar, at codon 19 of the DNMT3B protein (p.Asp19Glu). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.097
BayesDel_addAF	Benign	-0.030	T
BayesDel_noAF	Benign	-0.28
CADD	Benign	13
DANN	Benign	0.95
DEOGEN2	Benign	0.083	T;.;.;.;.;.
Eigen	Benign	-0.84
Eigen_PC	Benign	-0.74
FATHMM_MKL	Benign	0.22	N
LIST_S2	Benign	0.74	T;T;T;T;T;T
M_CAP	Uncertain	0.11	D
MetaRNN	Benign	0.061	T;T;T;T;T;T
MetaSVM	Uncertain	-0.13	T
MutationAssessor	Benign	0.81	L;L;L;L;L;.
MutationTaster	Benign	0.99	N;N;N;N;N;N;N;N
PrimateAI	Uncertain	0.49	T
PROVEAN	Benign	-0.49	N;N;N;N;N;N
REVEL	Benign	0.20
Sift	Benign	0.35	T;T;T;T;T;T
Sift4G	Benign	0.45	T;T;T;T;T;T
Polyphen		0.0080	B;B;B;.;.;B
Vest4		0.13
MutPred		0.35		Gain of sheet (P = 0.039);Gain of sheet (P = 0.039);Gain of sheet (P = 0.039);Gain of sheet (P = 0.039);Gain of sheet (P = 0.039);.;
MVP		0.41
MPC		0.68
ClinPred		0.28	T
GERP RS		2.4
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.053
gMVP		0.078

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: chr20-31368186;