12-49048660-T-C

Variant names:

• chr12-49048660-T-C
• rs1555195573
• NM_003482.4:c.4130A>G

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PM1 PM2 PM5 PP3

The NM_003482.4(KMT2D):​c.4130A>G​(p.Gln1377Arg) 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. 3/3 splice prediction tools predicting alterations to normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. Q1377P) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 33)
• Consequence: KMT2D NM_003482.4 missense, splice_region
• Scores: Splicing: ADA: 0.9995
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 7.95
• Publications: 0 publications found

Genes affected

KMT2D (HGNC:7133): (lysine methyltransferase 2D) The protein encoded by this gene is a histone methyltransferase that methylates the Lys-4 position of histone H3. The encoded protein is part of a large protein complex called ASCOM, which has been shown to be a transcriptional regulator of the beta-globin and estrogen receptor genes. Mutations in this gene have been shown to be a cause of Kabuki syndrome. [provided by RefSeq, Oct 2010]

KMT2D Gene-Disease associations (from GenCC):

• choanal atresia-athelia-hypothyroidism-delayed puberty-short stature syndrome

  Inheritance: AD Classification: DEFINITIVE, MODERATE Submitted by: Illumina, G2P
• Kabuki syndrome 1

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Laboratory for Molecular Medicine, ClinGen, Labcorp Genetics (formerly Invitae), Ambry Genetics
• branchial arch abnormalities, choanal atresia, athelia, hearing loss, and hypothyroidism syndrome

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• Kabuki syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 7 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 5 uncertain in NM_003482.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr12-49048660-T-G is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 547417.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_003482.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KMT2D	NM_003482.4	MANE Select	c.4130A>G	p.Gln1377Arg	missense splice_region	Exon 14 of 55	NP_003473.3

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KMT2D	ENST00000301067.12	TSL:5 MANE Select	c.4130A>G	p.Gln1377Arg	missense splice_region	Exon 14 of 55	ENSP00000301067.7
	KMT2D	ENST00000683543.2		c.4130A>G	p.Gln1377Arg	missense splice_region	Exon 14 of 56	ENSP00000506726.1
	KMT2D	ENST00000685166.1		c.4130A>G	p.Gln1377Arg	missense splice_region	Exon 13 of 54	ENSP00000509386.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 28

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Uncertain	0.15	D
BayesDel_noAF	Uncertain	-0.020
CADD	Pathogenic	34
DANN	Uncertain	0.98
DEOGEN2	Benign	0.25	T
Eigen	Pathogenic	0.75
Eigen_PC	Pathogenic	0.76
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.91	D
M_CAP	Pathogenic	0.36	D
MetaRNN	Pathogenic	0.82	D
MetaSVM	Uncertain	0.62	D
MutationAssessor	Uncertain	2.1	M
PhyloP100		7.9
PrimateAI	Pathogenic	0.83	D
PROVEAN	Uncertain	-3.3	D
REVEL	Pathogenic	0.66
Sift	Uncertain	0.018	D
Polyphen		1.0	D
Vest4		0.70
MutPred		0.45		Loss of catalytic residue at Q1377 (P = 0.0173)
MVP		0.81
MPC		2.5
ClinPred		0.93	D
GERP RS		5.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.32
gMVP		0.76
Mutation Taster		=9/91	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.98
Splicevardb		3.0
SpliceAI score (max)		0.71		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.71		Position offset: -37
DS_DL_spliceai		0.40		Position offset: -1

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

Other links and lift over

dbSNP: rs1555195573; hg19: chr12-49442443; COSMIC: COSV56458012; COSMIC: COSV56458012;