chr3-123664174-C-T

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PP3_Strong

The NM_053025.4(MYLK):​c.3916G>A​(p.Gly1306Ser) variant causes a missense change. The variant allele was found at a frequency of 0.0000124 in 1,614,034 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic 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. G1306A) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000013 ( 0 hom. )

Consequence

MYLK
NM_053025.4 missense

Scores

8
10
1

Clinical Significance

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

Conservation

PhyloP100: 6.11

Publications

1 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 4 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.977

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MYLKNM_053025.4 linkc.3916G>A p.Gly1306Ser missense_variant Exon 23 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.3916G>A p.Gly1306Ser missense_variant Exon 23 of 34 5 NM_053025.4 ENSP00000353452.3 Q15746-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152178
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000159
AC:
4
AN:
251350
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.000123
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000880
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000130
AC:
19
AN:
1461856
Hom.:
0
Cov.:
32
AF XY:
0.00000963
AC XY:
7
AN XY:
727226
show subpopulations
African (AFR)
AF:
0.000149
AC:
5
AN:
33480
American (AMR)
AF:
0.000112
AC:
5
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86258
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:
0.00000540
AC:
6
AN:
1111980
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.467
Heterozygous variant carriers
0
1
3
4
6
7
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
AF:
0.00000657
AC:
1
AN:
152178
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74348
show subpopulations
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
41446
American (AMR)
AF:
0.0000654
AC:
1
AN:
15284
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5184
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68022
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.375
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000264
ExAC
AF:
0.0000330
AC:
4

ClinVar

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

Submissions by phenotype

Aortic aneurysm, familial thoracic 7 Uncertain:2
Sep 02, 2022
Victorian Clinical Genetics Services, Murdoch Childrens Research Institute
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as VUS-3B. Following criteria are met: 0102 - Loss of function is a known mechanism of disease in this gene and is associated with autosomal dominant familial thoracic aortic aneurysm 7 (MIM#613780). It has also been reported for autosomal recessive megacystis-microcolon-intestinal hypoperistalsis syndrome 1 (MIM#249210), however this gene-disease association has not been established conclusively (PanelApp Australia). (I) 0107 - This gene is associated with autosomal dominant familial thoracic aortic aneurysm 7 (MIM#613780) although homozygotes with more early-onset severe disease have also been reported (PMID: 29544503; OMIM). It has also been associated with autosomal recessive megacystis-microcolon-intestinal hypoperistalsis syndrome 1 (MIM#249210), however this gene-disease association has not been established conclusively (PanelApp Australia). (I) 0112 - The familial thoracic aortic aneurysm 7 associated with this gene has incomplete penetrance (PMIDs: 29544503, 21055718; OMIM). (I) 0115 - Variants associated with familial thoracic aortic aneurysm 7 in this gene are known to have variable expressivity (PMIDs: 29544503, 21055718). (I) 0200 - Variant is predicted to result in a missense amino acid change from glycine to serine. (I) 0251 - This variant is heterozygous. (I) 0302 - Variant is present in gnomAD <0.001 for a dominant condition (v2 & v3: 5 heterozygotes, 0 homozygotes). (SP) 0309 - An alternative amino acid change at the same position has been observed in gnomAD (v2 & v3: 2 heterozygotes, 0 homozygotes). (I) 0502 - Missense variant with conflicting in silico predictions and uninformative conservation. (I) 0600 - Variant is located in the annotated immunoglobulin I-set domain (DECIPHER). (I) 0705 - No comparable missense variants have previous evidence for pathogenicity. (I) 0809 - Previous evidence of pathogenicity for this variant is inconclusive. It has been reported as a VUS by a clinical testing laboratory in three unrelated individuals with connective tissue features (mainly in skeletal tissue or joint) and an unaffected parent, an individual with non aortic-related artery disease, and an individual with a family history of aortic aneurysm who was positive for a known familial variant in an alternative gene associated with aortic aneurysm (ClinVar, personal communication). (I) 0905 - No published segregation evidence has been identified for this variant. (I) 1007 - No published functional evidence has been identified for this variant. (I) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

Jun 12, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with serine, which is neutral and polar, at codon 1306 of the MYLK protein (p.Gly1306Ser). This variant is present in population databases (rs755117377, 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: 409712). 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 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
Uncertain
0.52
BayesDel_addAF
Pathogenic
0.19
D
BayesDel_noAF
Pathogenic
0.28
CADD
Pathogenic
28
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.76
.;.;.;D;.;D;D
Eigen
Pathogenic
0.74
Eigen_PC
Uncertain
0.61
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Pathogenic
0.98
.;D;D;D;.;.;D
M_CAP
Uncertain
0.13
D
MetaRNN
Pathogenic
0.98
D;D;D;D;D;D;D
MetaSVM
Uncertain
0.59
D
MutationAssessor
Pathogenic
3.6
H;.;H;H;.;H;.
PhyloP100
6.1
PrimateAI
Uncertain
0.63
T
PROVEAN
Pathogenic
-5.4
D;.;D;D;D;D;D
REVEL
Pathogenic
0.74
Sift
Uncertain
0.019
D;.;D;D;D;D;D
Sift4G
Uncertain
0.0040
D;D;D;D;D;D;.
Polyphen
1.0
D;D;D;D;D;D;.
Vest4
0.91
MutPred
0.94
Gain of sheet (P = 0.1208);.;Gain of sheet (P = 0.1208);Gain of sheet (P = 0.1208);.;Gain of sheet (P = 0.1208);.;
MVP
0.91
MPC
0.27
ClinPred
0.95
D
GERP RS
4.0
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.39
gMVP
0.77
Mutation Taster
=27/73
disease causing

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: rs755117377; hg19: chr3-123383021; COSMIC: COSV60604781; COSMIC: COSV60604781; API