chr19-35718038-G-A

Variant names:

• chr19-35718038-G-A
• NM_014727.3:c.20G>A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_014727.3(KMT2B):​c.20G>A​(p.Gly7Asp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: KMT2B NM_014727.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.28

Genes affected

KMT2B (HGNC:15840): (lysine methyltransferase 2B) This gene encodes a protein which contains multiple domains including a CXXC zinc finger, three PHD zinc fingers, two FY-rich domains, and a SET (suppressor of variegation, enhancer of zeste, and trithorax) domain. The SET domain is a conserved C-terminal domain that characterizes proteins of the MLL (mixed-lineage leukemia) family. This gene is ubiquitously expressed in adult tissues. It is also amplified in solid tumor cell lines, and may be involved in human cancer. Two alternatively spliced transcript variants encoding distinct isoforms have been reported for this gene, however, the full length nature of the shorter transcript is not known. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.3286702).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KMT2B	NM_014727.3	c.20G>A	p.Gly7Asp	missense_variant	Exon 1 of 37	ENST00000420124.4	NP_055542.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
KMT2B	ENST00000420124.4	c.20G>A	p.Gly7Asp	missense_variant	Exon 1 of 37	1	NM_014727.3	ENSP00000398837.2
KMT2B	ENST00000673918.2	c.20G>A	p.Gly7Asp	missense_variant	Exon 1 of 37			ENSP00000501283.1
KMT2B	ENST00000687718.1	n.20G>A		non_coding_transcript_exon_variant	Exon 1 of 3			ENSP00000510535.1
KMT2B	ENST00000692961.1	n.20G>A		non_coding_transcript_exon_variant	Exon 1 of 36			ENSP00000509289.1

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

not provided Uncertain:1

Aug 27, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with aspartic acid, which is acidic and polar, at codon 7 of the KMT2B protein (p.Gly7Asp). 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. This variant has not been reported in the literature in individuals affected with KMT2B-related conditions. Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt KMT2B protein function with a positive predictive value of 80%. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.60
BayesDel_addAF	Uncertain	0.044	T
BayesDel_noAF	Benign	-0.17
CADD	Uncertain	25
DANN	Benign	0.91
DEOGEN2	Benign	0.025	T
Eigen	Benign	-0.46
Eigen_PC	Benign	-0.48
FATHMM_MKL	Benign	0.34	N
LIST_S2	Benign	0.37	T
M_CAP	Pathogenic	0.90	D
MetaRNN	Benign	0.33	T
MetaSVM	Benign	-0.68	T
MutationAssessor	Benign	0.0	N
PrimateAI	Pathogenic	0.90	D
PROVEAN	Benign	-0.88	N
REVEL	Uncertain	0.37
Sift	Pathogenic	0.0	D
Sift4G	Uncertain	0.0030	D
Polyphen		0.67	P
Vest4		0.38
MutPred		0.15		Loss of catalytic residue at S9 (P = 0.0368);
MVP		0.37
ClinPred		0.36	T
GERP RS		1.0
Varity_R		0.15
gMVP		0.14

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: chr19-36208940;