Genetic Variant MYLK2:p.Ile155Phe (chr20-31820536-A-T) – ACMG Classification: Likely_benign (-6 pts)

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 0P and 6B. BP4_ModerateBS2

The NM_033118.4(MYLK2):c.463A>T(p.Ile155Phe) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000543 in 1,600,880 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000046 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000055 ( 0 hom. )

Consequence

MYLK2
NM_033118.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: -1.17

Variant links:

Genes affected

MYLK2 (HGNC:16243): (myosin light chain kinase 2) This gene encodes a myosin light chain kinase, a calcium/calmodulin dependent enzyme, that is exclusively expressed in adult skeletal muscle. [provided by RefSeq, Jul 2008]

MYLK2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -6 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.11862138).

BS2

High AC in GnomAd4 at 7 AD,Digenic gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MYLK2	NM_033118.4 link	c.463A>T	p.Ile155Phe	missense_variant	Exon 3 of 13	ENST00000375985.5	NP_149109.1	Q9H1R3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MYLK2	ENST00000375985.5 link	c.463A>T	p.Ile155Phe	missense_variant	Exon 3 of 13	1	NM_033118.4	ENSP00000365152.4		Q9H1R3
MYLK2	ENST00000375994.6 link	c.463A>T	p.Ile155Phe	missense_variant	Exon 2 of 12	1		ENSP00000365162.2		Q9H1R3

Frequencies

GnomAD3 genomes

AF:

0.0000460

AC:

AN:

152236

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

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:

0.0000882

Gnomad OTH

AF:

0.000478

GnomAD3 exomes

AF:

0.0000588

AC:

AN:

238286

Hom.:

AF XY:

0.0000384

AC XY:

AN XY:

130074

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.000145

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000631

Gnomad OTH exome

AF:

0.000334

GnomAD4 exome

AF:

0.0000552

AC:

AN:

1448644

Hom.:

Cov.:

AF XY:

0.0000555

AC XY:

AN XY:

721094

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.000179

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:

0.0000612

Gnomad4 OTH exome

AF:

0.0000663

GnomAD4 genome

AF:

0.0000460

AC:

AN:

152236

Hom.:

Cov.:

AF XY:

0.0000403

AC XY:

AN XY:

74382

show subpopulations

Gnomad4 AFR

AF:

0.00

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:

0.0000882

Gnomad4 OTH

AF:

0.000478

Bravo

AF:

0.0000340

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000116

AC:

ExAC

AF:

0.0000413

AC:

EpiCase

AF:

0.000273

EpiControl

AF:

0.000119

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Mar 16, 2015

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.Ile155Phe variant in MYLK2 has been identified by our laboratory in 1 infa nt with mitral and tricuspid valve dysplasia. This variant has also been identif ied in 4/62662 of European chromosomes by the Exome Aggregation Consortium (ExAC , http://exac.broadinstitute.org; dbSNP rs140233643). Computational prediction t ools and conservation analysis suggest that the p.Ile155Phe variant may not impa ct the protein, though this information is not predictive enough to rule out pat hogenicity. In summary, the clinical significance of the p.Ile155Phe variant is uncertain. -

Cardiomyopathy

Uncertain:1

Dec 21, 2017

CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Hypertrophic cardiomyopathy 1

Uncertain:1

Nov 28, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces isoleucine, which is neutral and non-polar, with phenylalanine, which is neutral and non-polar, at codon 155 of the MYLK2 protein (p.Ile155Phe). This variant is present in population databases (rs140233643, gnomAD 0.02%). This variant has not been reported in the literature in individuals affected with MYLK2-related conditions. ClinVar contains an entry for this variant (Variation ID: 164499). 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 not expected to disrupt MYLK2 protein function with a negative 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

Benign

0.096

BayesDel_addAF

Benign

-0.38

BayesDel_noAF

Benign

-0.49

CADD

Benign

1.5

DANN

Benign

0.86

DEOGEN2

Benign

0.27

T;T

Eigen

Benign

-0.77

Eigen_PC

Benign

-0.88

FATHMM_MKL

Benign

0.080

LIST_S2

Benign

0.61

.;T

M_CAP

Benign

0.069

MetaRNN

Benign

0.12

T;T

MetaSVM

Benign

-0.99

MutationAssessor

Benign

1.9

L;L

PrimateAI

Benign

0.34

PROVEAN

Benign

-1.3

N;N

REVEL

Benign

0.081

Sift

Uncertain

0.0030

D;D

Sift4G

Benign

0.33

T;T

Polyphen

0.64

P;P

Vest4

0.16

MVP

0.48

MPC

0.23

ClinPred

0.071

GERP RS

-0.63

Varity_R

0.16

gMVP

0.093

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over