9-137619030-T-G

Variant names:

• chr9-137619030-T-G
• rs1185800023
• NM_024757.5:c.2T>G

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PVS1_Supporting PM2

The NM_024757.5(EHMT1):​c.2T>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 0.00000122 in 821,594 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 Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0000012 (0 hom.)
• Consequence: EHMT1 NM_024757.5 start_lost
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.599

Genes affected

EHMT1 (HGNC:24650): (euchromatic histone lysine methyltransferase 1) The protein encoded by this gene is a histone methyltransferase that methylates the lysine-9 position of histone H3. This action marks the genomic region packaged with these methylated histones for transcriptional repression. This protein may be involved in the silencing of MYC- and E2F-responsive genes and therefore could play a role in the G0/G1 cell cycle transition. Defects in this gene are a cause of chromosome 9q subtelomeric deletion syndrome (9q-syndrome, also known as Kleefstra syndrome). Alternative splicing results in multiple transcript variants. [provided by RefSeq, Aug 2017]

ENSG00000283411 (HGNC:):

ARRDC1-AS1 (HGNC:23395): (ARRDC1 antisense RNA 1) This transcribed locus is thought to be non-coding. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jun 2014]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PVS1: Start lost variant, no pathogenic variants between lost start and next in-frame start position. Next in-frame start position is after 32 codons. Genomic position: 137716634. Lost 0.024 part of the original CDS.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
EHMT1	NM_024757.5	c.2T>G	p.Met1?	start_lost	Exon 1 of 27	ENST00000460843.6	NP_079033.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
EHMT1	ENST00000460843.6	c.2T>G	p.Met1?	start_lost	Exon 1 of 27	5	NM_024757.5	ENSP00000417980.1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome AF: 0.00000122 AC: 1 AN: 821594 Hom.: 0 Cov.: 17 AF XY: 0.00 AC XY: 0 AN XY: 379920

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: 0.00000133

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Kleefstra syndrome 1 Uncertain:1

Jun 19, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change affects the initiator methionine of the EHMT1 mRNA. The next in-frame methionine is located at codon 32. The frequency data for this variant in the population databases is considered unreliable, as metrics indicate insufficient coverage at this position in the gnomAD database. 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. ClinVar contains an entry for this variant (Variation ID: 1021030). This variant has not been reported in the literature in individuals affected with EHMT1-related conditions. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Benign	-0.20
CADD	Benign	23
DANN	Benign	0.96
DEOGEN2	Benign	0.063	T;.;T
Eigen	Benign	-0.38
Eigen_PC	Benign	-0.42
FATHMM_MKL	Benign	0.13	N
LIST_S2	Uncertain	0.90	D;D;D
M_CAP	Pathogenic	0.98	D
MetaRNN	Pathogenic	0.97	D;D;D
MetaSVM	Benign	-0.65	T
PROVEAN	Benign	-0.68	N;N;.
REVEL	Benign	0.24
Sift	Pathogenic	0.0	D;D;.
Sift4G	Pathogenic	0.0	D;D;.
Polyphen		0.0	B;P;.
Vest4		0.61
MutPred		0.99		Gain of methylation at M1 (P = 0.0106);Gain of methylation at M1 (P = 0.0106);Gain of methylation at M1 (P = 0.0106);
MVP		0.76
ClinPred		0.24	T
GERP RS		1.5
Varity_R		0.84
gMVP		0.17

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: rs1185800023; hg19: chr9-140513482;