rs55672414

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 1P and 0B. PP2

The NM_053025.4(MYLK):c.1612C>T(p.Arg538Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000458 in 1,614,138 control chromosomes in the GnomAD database, including 1 homozygotes. 13/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R538Q) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.00021 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000029 ( 1 hom. )

Consequence

MYLK
NM_053025.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4

Conservation

PhyloP100: 1.65

Variant links:

Genes affected

MYLK (HGNC:7590): (myosin light chain kinase) This gene, a muscle member of the immunoglobulin gene superfamily, encodes myosin light chain kinase which is a calcium/calmodulin dependent enzyme. This kinase phosphorylates myosin regulatory light chains to facilitate myosin interaction with actin filaments to produce contractile activity. This gene encodes both smooth muscle and nonmuscle isoforms. In addition, using a separate promoter in an intron in the 3' region, it encodes telokin, a small protein identical in sequence to the C-terminus of myosin light chain kinase, that is independently expressed in smooth muscle and functions to stabilize unphosphorylated myosin filaments. A pseudogene is located on the p arm of chromosome 3. Four transcript variants that produce four isoforms of the calcium/calmodulin dependent enzyme have been identified as well as two transcripts that produce two isoforms of telokin. Additional variants have been identified but lack full length transcripts. [provided by RefSeq, Jul 2008]

MYLK links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 1 ACMG points.

PP2

Missense variant where missense usually causes diseases, MYLK

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MYLK	NM_053025.4 linkuse as main transcript	c.1612C>T	p.Arg538Trp	missense_variant	12/34	ENST00000360304.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MYLK	ENST00000360304.8 linkuse as main transcript	c.1612C>T	p.Arg538Trp	missense_variant	12/34	5	NM_053025.4	P4	Q15746-1

Frequencies

GnomAD3 genomes

AF:

0.000164

AC:

AN:

152196

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000531

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.000193

Gnomad SAS

AF:

0.000207

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.000478

GnomAD3 exomes

AF:

0.0000279

AC:

AN:

250938

Hom.:

AF XY:

0.0000295

AC XY:

AN XY:

135660

show subpopulations

Gnomad AFR exome

AF:

0.000309

Gnomad AMR exome

AF:

0.00

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:

0.0000176

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000287

AC:

AN:

1461824

Hom.:

Cov.:

AF XY:

0.0000289

AC XY:

AN XY:

727204

show subpopulations

Gnomad4 AFR exome

AF:

0.000747

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:

0.00000270

Gnomad4 OTH exome

AF:

0.000232

GnomAD4 genome

AF:

0.000210

AC:

AN:

152314

Hom.:

Cov.:

AF XY:

0.000255

AC XY:

AN XY:

74470

show subpopulations

Gnomad4 AFR

AF:

0.000697

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.000193

Gnomad4 SAS

AF:

0.000207

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.000473

Alfa

AF:

0.0000658

Hom.:

Bravo

AF:

0.000208

ESP6500AA

AF:

0.000454

AC:

ESP6500EA

AF:

0.00

AC:

ExAC

AF:

0.0000247

AC:

Asia WGS

AF:

0.00144

AC:

AN:

3478

EpiCase

AF:

0.00

EpiControl

AF:

0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Jul 21, 2023

- -

Aortic aneurysm, familial thoracic 7

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Oct 17, 2023

This sequence change replaces arginine, which is basic and polar, with tryptophan, which is neutral and slightly polar, at codon 538 of the MYLK protein (p.Arg538Trp). This variant is present in population databases (rs55672414, gnomAD 0.02%). This variant has not been reported in the literature in individuals affected with MYLK-related conditions. ClinVar contains an entry for this variant (Variation ID: 539078). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt MYLK protein function. 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. -

Familial thoracic aortic aneurysm and aortic dissection

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Sep 07, 2021

The p.R538W variant (also known as c.1612C>T), located in coding exon 9 of the MYLK gene, results from a C to T substitution at nucleotide position 1612. The arginine at codon 538 is replaced by tryptophan, an amino acid with dissimilar properties. This amino acid position is conserved. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Aortic aneurysm, familial thoracic 7;C5542316:Megacystis-microcolon-intestinal hypoperistalsis syndrome 1

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Jul 28, 2021

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.31

BayesDel_addAF

Benign

-0.30

BayesDel_noAF

Benign

-0.37

Cadd

Benign

Dann

Uncertain

1.0

Eigen

Benign

0.070

Eigen_PC

Benign

-0.024

FATHMM_MKL

Benign

0.44

M_CAP

Benign

0.069

MetaRNN

Uncertain

0.45

T;T;T;T;T;T

MetaSVM

Benign

-0.47

MutationAssessor

Benign

1.7

L;.;L;L;.;L

MutationTaster

Benign

1.0

N;N;N;N;N

PrimateAI

Benign

0.21

PROVEAN

Benign

-1.9

N;.;N;N;N;N

REVEL

Benign

0.23

Sift

Uncertain

0.013

D;.;D;D;D;D

Sift4G

Uncertain

0.011

D;D;D;D;D;D

Polyphen

0.99

D;P;D;D;P;D

Vest4

0.28

MVP

0.85

MPC

0.55

ClinPred

0.25

GERP RS

3.9

Varity_R

0.31

gMVP

0.45

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