rs140148380

Variant summary

Our verdict is Benign. The variant received -13 ACMG points: 0P and 13B. BP4_StrongBP6BS1BS2

The NM_053025.4(MYLK):​c.399G>T​(p.Gln133His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00196 in 1,613,998 control chromosomes in the GnomAD database, including 10 homozygotes. In-silico tool predicts a benign outcome for this variant. 16/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.0018 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0020 ( 10 hom. )

Consequence

MYLK
NM_053025.4 missense

Scores

2
17

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:15

Conservation

PhyloP100: -0.697

Publications

6 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: Benign. The variant received -13 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.007837027).
BP6
Variant 3-123739976-C-A is Benign according to our data. Variant chr3-123739976-C-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 263911.
BS1
Variant frequency is greater than expected in population sas. GnomAd4 allele frequency = 0.00175 (267/152334) while in subpopulation SAS AF = 0.00415 (20/4820). AF 95% confidence interval is 0.00275. There are 0 homozygotes in GnomAd4. There are 136 alleles in the male GnomAd4 subpopulation. Median coverage is 33. This position passed quality control check.
BS2
High Homozygotes in GnomAdExome4 at 10 AD,AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MYLKNM_053025.4 linkc.399G>T p.Gln133His missense_variant Exon 6 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.399G>T p.Gln133His missense_variant Exon 6 of 34 5 NM_053025.4 ENSP00000353452.3 Q15746-1

Frequencies

GnomAD3 genomes
AF:
0.00175
AC:
267
AN:
152216
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.000555
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00255
Gnomad ASJ
AF:
0.00115
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00415
Gnomad FIN
AF:
0.00151
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00237
Gnomad OTH
AF:
0.00191
GnomAD2 exomes
AF:
0.00181
AC:
456
AN:
251440
AF XY:
0.00196
show subpopulations
Gnomad AFR exome
AF:
0.000246
Gnomad AMR exome
AF:
0.00173
Gnomad ASJ exome
AF:
0.000496
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00189
Gnomad NFE exome
AF:
0.00214
Gnomad OTH exome
AF:
0.00228
GnomAD4 exome
AF:
0.00198
AC:
2898
AN:
1461664
Hom.:
10
Cov.:
31
AF XY:
0.00206
AC XY:
1495
AN XY:
727126
show subpopulations
African (AFR)
AF:
0.000299
AC:
10
AN:
33478
American (AMR)
AF:
0.00165
AC:
74
AN:
44720
Ashkenazi Jewish (ASJ)
AF:
0.000727
AC:
19
AN:
26132
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39700
South Asian (SAS)
AF:
0.00332
AC:
286
AN:
86238
European-Finnish (FIN)
AF:
0.00230
AC:
123
AN:
53410
Middle Eastern (MID)
AF:
0.00104
AC:
6
AN:
5764
European-Non Finnish (NFE)
AF:
0.00203
AC:
2261
AN:
1111840
Other (OTH)
AF:
0.00195
AC:
118
AN:
60382
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.472
Heterozygous variant carriers
0
169
338
506
675
844
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
86
172
258
344
430
<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
AF:
0.00175
AC:
267
AN:
152334
Hom.:
0
Cov.:
33
AF XY:
0.00183
AC XY:
136
AN XY:
74480
show subpopulations
African (AFR)
AF:
0.000553
AC:
23
AN:
41574
American (AMR)
AF:
0.00255
AC:
39
AN:
15304
Ashkenazi Jewish (ASJ)
AF:
0.00115
AC:
4
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5178
South Asian (SAS)
AF:
0.00415
AC:
20
AN:
4820
European-Finnish (FIN)
AF:
0.00151
AC:
16
AN:
10620
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00237
AC:
161
AN:
68044
Other (OTH)
AF:
0.00189
AC:
4
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.512
Heterozygous variant carriers
0
18
35
53
70
88
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
4
8
12
16
20
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00191
Hom.:
2
Bravo
AF:
0.00161
TwinsUK
AF:
0.00108
AC:
4
ALSPAC
AF:
0.00156
AC:
6
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.00198
AC:
17
ExAC
AF:
0.00173
AC:
210
Asia WGS
AF:
0.000577
AC:
2
AN:
3478
EpiCase
AF:
0.00180
EpiControl
AF:
0.00202

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:1Benign:15
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Benign:7
-
Genome Diagnostics Laboratory, Amsterdam University Medical Center
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

May 07, 2021
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

-
Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Nov 03, 2021
Institute for Clinical Genetics, University Hospital TU Dresden, University Hospital TU Dresden
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Nov 22, 2024
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

-
Genome Diagnostics Laboratory, University Medical Center Utrecht
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Jun 01, 2025
CeGaT Center for Human Genetics Tuebingen
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

MYLK: BP4, BS2 -

not specified Benign:3
Jun 13, 2017
Molecular Diagnostic Laboratory for Inherited Cardiovascular Disease, Montreal Heart Institute
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Apr 27, 2020
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: MYLK c.399G>T (p.Gln133His) results in a non-conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 0.0018 in 251440 control chromosomes in the gnomAD database, including 3 homozygotes. The observed variant frequency is approximately 725 fold of the estimated maximal expected allele frequency for a pathogenic variant in MYLK causing Aortopathy phenotype (2.5e-06), strongly suggesting that the variant is benign. c.399G>T has been reported in the literature (Milewicz_2017). This report however, does not provide unequivocal conclusions about association of the variant with Aortopathy. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Eight ClinVar submitters (evaluation after 2014) cite the variant as likely benign/benign (n=7) or uncertain significance (n=1). Based on the evidence outlined above, the variant was classified as likely benign. -

Nov 03, 2016
Eurofins Ntd Llc (ga)
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Aortic aneurysm, familial thoracic 7 Uncertain:1Benign:1
Jan 13, 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. -

Jan 30, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Familial thoracic aortic aneurysm and aortic dissection Benign:2
Dec 01, 2017
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Feb 16, 2019
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. -

Congenital aneurysm of ascending aorta Benign:1
Oct 01, 2016
CSER _CC_NCGL, University of Washington
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:research

Found in patient having exome sequencing for an unrelated indication. No known history of familial thoracic aortic aneurysm. This interpretation considers GERP score and allele frequency data, in addition to published reports of the variant in the literature, available at the time of review. -

MYLK-related disorder Benign:1
May 29, 2019
PreventionGenetics, part of Exact Sciences
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.35
BayesDel_addAF
Benign
-0.46
T
BayesDel_noAF
Benign
-0.44
CADD
Benign
3.3
DANN
Benign
0.95
DEOGEN2
Benign
0.22
.;.;.;T;.;T
Eigen
Benign
-1.2
Eigen_PC
Benign
-1.1
FATHMM_MKL
Benign
0.11
N
LIST_S2
Benign
0.69
.;T;T;T;.;.
M_CAP
Benign
0.026
D
MetaRNN
Benign
0.0078
T;T;T;T;T;T
MetaSVM
Benign
-1.0
T
MutationAssessor
Benign
0.20
N;N;N;N;N;N
PhyloP100
-0.70
PrimateAI
Benign
0.34
T
PROVEAN
Benign
-1.3
N;.;N;N;N;N
REVEL
Benign
0.044
Sift
Benign
0.13
T;.;T;T;T;T
Sift4G
Uncertain
0.025
D;D;D;D;D;D
Polyphen
0.019
B;B;B;B;B;B
Vest4
0.20
MutPred
0.40
Loss of ubiquitination at K129 (P = 0.0615);Loss of ubiquitination at K129 (P = 0.0615);Loss of ubiquitination at K129 (P = 0.0615);Loss of ubiquitination at K129 (P = 0.0615);Loss of ubiquitination at K129 (P = 0.0615);Loss of ubiquitination at K129 (P = 0.0615);
MVP
0.35
MPC
0.25
ClinPred
0.0065
T
GERP RS
-1.9
Varity_R
0.043
gMVP
0.47
Mutation Taster
=100/0
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.020
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: rs140148380; hg19: chr3-123458823; API