19-35718061-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_014727.3(KMT2B):c.43T>C(p.Ser15Pro) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000686 in 145,798 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency: Genomes: 𝑓 0.0000069 (0 hom., cov: 32)
• Consequence: KMT2B NM_014727.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 0.747

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 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.16526684).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
KMT2B	NM_014727.3	c.43T>C	p.Ser15Pro	missense_variant	1/37	ENST00000420124.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
KMT2B	ENST00000420124.4	c.43T>C	p.Ser15Pro	missense_variant	1/37	1	NM_014727.3	P2
KMT2B	ENST00000673918.2	c.43T>C	p.Ser15Pro	missense_variant	1/37			A2
KMT2B	ENST00000692961.1	c.43T>C	p.Ser15Pro	missense_variant, NMD_transcript_variant	1/36
KMT2B	ENST00000687718.1	c.43T>C	p.Ser15Pro	missense_variant, NMD_transcript_variant	1/3

Frequencies

GnomAD3 genomes AF: 0.00000686 AC: 1 AN: 145798 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000246

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome Cov.: 31

GnomAD4 genome AF: 0.00000686 AC: 1 AN: 145798 Hom.: 0 Cov.: 32 AF XY: 0.0000141 AC XY: 1 AN XY: 70902

Gnomad4 AFR AF: 0.0000246

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jan 23, 2024

The c.43T>C (p.S15P) alteration is located in exon 1 (coding exon 1) of the KMT2B gene. This alteration results from a T to C substitution at nucleotide position 43, causing the serine (S) at amino acid position 15 to be replaced by a proline (P). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jul 06, 2022

This sequence change replaces serine, which is neutral and polar, with proline, which is neutral and non-polar, at codon 15 of the KMT2B protein (p.Ser15Pro). 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 are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Not Available"; Align-GVGD: "Class C0"). This variant has not been reported in the literature in individuals affected with KMT2B-related conditions. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.14
BayesDel_addAF	Uncertain	0.033	T
BayesDel_noAF	Benign	-0.19
Cadd	Uncertain	23
Dann	Benign	0.57
DEOGEN2	Benign	0.035	T
Eigen	Benign	-0.68
Eigen_PC	Benign	-0.61
FATHMM_MKL	Benign	0.12	N
LIST_S2	Benign	0.34	T
M_CAP	Pathogenic	0.82	D
MetaRNN	Benign	0.17	T
MetaSVM	Benign	-0.71	T
MutationAssessor	Benign	0.0	N
MutationTaster	Benign	1.0	N;N;N
PrimateAI	Pathogenic	0.91	D
PROVEAN	Benign	-1.4	N
REVEL	Benign	0.27
Sift	Pathogenic	0.0	D
Sift4G	Uncertain	0.011	D
Polyphen		0.0080	B
Vest4		0.30
MutPred		0.14		Loss of phosphorylation at S15 (P = 0.0063);
MVP		0.43
ClinPred		0.32	T
GERP RS		2.0
Varity_R		0.22
gMVP		0.11

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: rs1306123854; hg19: chr19-36208963;