rs754479443

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 0P and 4B. BP4_Strong

The NM_053025.4(MYLK):​c.643A>G​(p.Met215Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000889 in 1,461,878 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 17/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. M215T) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0000089 ( 0 hom. )

Consequence

MYLK
NM_053025.4 missense

Scores

19

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:4B:1

Conservation

PhyloP100: -0.218

Publications

0 publications found
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 Gene-Disease associations (from GenCC):
  • aortic aneurysm, familial thoracic 7
    Inheritance: AD Classification: STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics
  • familial thoracic aortic aneurysm and aortic dissection
    Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, ClinGen
  • megacystis-microcolon-intestinal hypoperistalsis syndrome 1
    Inheritance: AR Classification: STRONG Submitted by: G2P
  • connective tissue disorder
    Inheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
  • megacystis-microcolon-intestinal hypoperistalsis syndrome
    Inheritance: AD, AR Classification: SUPPORTIVE, LIMITED Submitted by: Orphanet, Ambry Genetics

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -4 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.035667628).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MYLKNM_053025.4 linkc.643A>G p.Met215Val missense_variant Exon 8 of 34 ENST00000360304.8 NP_444253.3 Q15746-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MYLKENST00000360304.8 linkc.643A>G p.Met215Val missense_variant Exon 8 of 34 5 NM_053025.4 ENSP00000353452.3 Q15746-1

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.0000159
AC:
4
AN:
251480
AF XY:
0.0000221
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000867
Gnomad ASJ exome
AF:
0.0000992
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000889
AC:
13
AN:
1461878
Hom.:
0
Cov.:
32
AF XY:
0.00000825
AC XY:
6
AN XY:
727234
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.0000894
AC:
4
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86246
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53416
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000719
AC:
8
AN:
1112012
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.494
Heterozygous variant carriers
0
1
2
4
5
6
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
Cov.:
32
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378
ExAC
AF:
0.0000165
AC:
2

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:4Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Aortic aneurysm, familial thoracic 7 Uncertain:2
Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Nov 17, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces methionine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 215 of the MYLK protein (p.Met215Val). This variant is present in population databases (rs754479443, gnomAD 0.01%). 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: 342902). 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 with a negative predictive value of 95%. 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. -

not provided Uncertain:2
Jan 16, 2021
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The MYLK c.643A>G; p.Met215Val variant (rs754479443), to our knowledge, is not reported in the medical literature but is reported in ClinVar (Variation ID: 342902). This variant is found on only four chromosomes (4/251480 alleles) in the Genome Aggregation Database. The methionine at codon 215 is weakly conserved, and computational analyses predict that this variant is neutral (REVEL: 0.083). However, due to limited information, the clinical significance of the p.Met215Val variant is uncertain at this time. -

Oct 19, 2020
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Has not been previously published as pathogenic or benign to our knowledge; Reported in ClinVar as a variant of uncertain significance (ClinVar Variant ID# 342902; Landrum et al., 2016); Not observed at a significant frequency in large population cohorts (Lek et al., 2016); In silico analysis supports that this missense variant does not alter protein structure/function -

Familial thoracic aortic aneurysm and aortic dissection Benign:1
Jun 22, 2022
Ambry Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.17
BayesDel_addAF
Benign
-0.31
T
BayesDel_noAF
Benign
-0.50
CADD
Benign
1.1
DANN
Benign
0.57
DEOGEN2
Benign
0.22
.;.;.;T;.;T
Eigen
Benign
-1.5
Eigen_PC
Benign
-1.4
FATHMM_MKL
Benign
0.034
N
LIST_S2
Benign
0.64
.;T;T;T;.;.
M_CAP
Benign
0.0079
T
MetaRNN
Benign
0.036
T;T;T;T;T;T
MetaSVM
Benign
-1.1
T
MutationAssessor
Benign
-0.60
N;N;N;N;N;N
PhyloP100
-0.22
PrimateAI
Benign
0.28
T
PROVEAN
Benign
-0.33
N;.;N;N;N;N
REVEL
Benign
0.083
Sift
Benign
0.85
T;.;T;T;T;T
Sift4G
Benign
0.82
T;T;T;T;T;T
Polyphen
0.0010
B;B;B;B;B;B
Vest4
0.23
MutPred
0.42
Gain of catalytic residue at M215 (P = 0.1302);Gain of catalytic residue at M215 (P = 0.1302);Gain of catalytic residue at M215 (P = 0.1302);Gain of catalytic residue at M215 (P = 0.1302);Gain of catalytic residue at M215 (P = 0.1302);Gain of catalytic residue at M215 (P = 0.1302);
MVP
0.38
MPC
0.21
ClinPred
0.011
T
GERP RS
-6.0
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.033
gMVP
0.33
Mutation Taster
=95/5
polymorphism

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

Other links and lift over

dbSNP: rs754479443; hg19: chr3-123456336; API