3-123638190-A-T

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_053025.4(MYLK):​c.4842T>A​(p.Asn1614Lys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,332 control chromosomes in the GnomAD database, with no homozygous occurrence. 13/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. N1614N) has been classified as Benign.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

MYLK
NM_053025.4 missense

Scores

1
5
12

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 0.0920

Publications

21 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-AS1 (HGNC:42440): (MYLK antisense RNA 1)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MYLKNM_053025.4 linkc.4842T>A p.Asn1614Lys missense_variant Exon 29 of 34 ENST00000360304.8 NP_444253.3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MYLKENST00000360304.8 linkc.4842T>A p.Asn1614Lys missense_variant Exon 29 of 34 5 NM_053025.4 ENSP00000353452.3

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.00000399
AC:
1
AN:
250898
AF XY:
0.00000737
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.00000205
AC:
3
AN:
1461332
Hom.:
0
Cov.:
33
AF XY:
0.00000275
AC XY:
2
AN XY:
726964
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
33460
American (AMR)
AF:
0.0000448
AC:
2
AN:
44662
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39684
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86226
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53416
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5444
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111948
Other (OTH)
AF:
0.00
AC:
0
AN:
60356
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.00131091), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.392
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
32
Alfa
AF:
0.00
Hom.:
4469

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Uncertain:1
Jan 17, 2022
Phosphorus, Inc.
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense variant results in an amino acid substitution of asparagine with lysine at codon 1614 of the MYLK gene (NM_053025.3). The variant has no entry in ClinVar and has occurred in GnomAD with a total MAF of 0.0004%. This position is not conserved. In silico functional algorithms agreed, with PolyPhen calling it possibly damaging, and SIFT deleterious, but no functional studies were performed to confirm these predictions. The variant has not occurred in literature associated with disease. Considering that this is a rare variant, whose impact on the protein and association with disease are unknown, it has been classified as a Variant of Uncertain Significance.

Aortic aneurysm, familial thoracic 7 Uncertain:1
May 27, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces asparagine, which is neutral and polar, with lysine, which is basic and polar, at codon 1614 of the MYLK protein (p.Asn1614Lys). This variant is present in population databases (no rsID available, gnomAD no frequency). This variant has not been reported in the literature in individuals affected with MYLK-related conditions. 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.

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.48
BayesDel_addAF
Benign
-0.13
T
BayesDel_noAF
Benign
-0.42
CADD
Benign
4.2
DANN
Uncertain
0.98
DEOGEN2
Benign
0.0
.;.;.;T;.;T
Eigen
Benign
-0.54
Eigen_PC
Benign
-0.55
FATHMM_MKL
Uncertain
0.94
D
LIST_S2
Benign
0.0
.;T;D;T;.;.
M_CAP
Benign
0.047
D
MetaRNN
Uncertain
0.62
D;D;D;D;D;D
MetaSVM
Benign
-0.79
T
MutationAssessor
Benign
0.63
N;.;N;N;.;N
PhyloP100
0.092
PrimateAI
Pathogenic
0.81
D
PROVEAN
Benign
-2.0
N;.;N;N;N;N
REVEL
Benign
0.22
Sift
Benign
0.060
T;.;T;T;T;T
Sift4G
Uncertain
0.053
T;T;T;T;T;T
Vest4
0.29
ClinPred
0.27
T
GERP RS
-0.076
Varity_R
0.056
gMVP
0.52
Mutation Taster
=70/30
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs820463; hg19: chr3-123357037; API