chr3-123649203-G-C

Position:

chr3-123649203-G-C

Variant summary

Our verdict is Benign. Variant got -20 ACMG points: 0P and 20B. BP4_StrongBP6_Very_StrongBS1BS2

The NM_053025.4(MYLK):c.4289-9C>G variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000827 in 1,612,298 control chromosomes in the GnomAD database, including 10 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.0042 ( 7 hom., cov: 32)

Exomes 𝑓: 0.00047 ( 3 hom. )

Consequence

MYLK
NM_053025.4 intron

Scores

Splicing: ADA: 0.0005321

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:7

Conservation

PhyloP100: 0.519

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:

LOC124909421 (HGNC:):

LOC124909421 links:

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ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -20 ACMG points.

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.75).

BP6

Variant 3-123649203-G-C is Benign according to our data. Variant chr3-123649203-G-C is described in ClinVar as [Likely_benign]. Clinvar id is 415754.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr3-123649203-G-C is described in Lovd as [Benign].

BS1

Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.00425 (646/152120) while in subpopulation AFR AF= 0.0149 (620/41488). AF 95% confidence interval is 0.014. There are 7 homozygotes in gnomad4. There are 295 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck.

BS2

High Homozygotes in GnomAd4 at 7 AD,AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MYLK	NM_053025.4 linkuse as main transcript	c.4289-9C>G		intron_variant		ENST00000360304.8	NP_444253.3	Q15746-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MYLK	ENST00000360304.8 linkuse as main transcript	c.4289-9C>G		intron_variant		5	NM_053025.4	ENSP00000353452.3		Q15746-1

Frequencies

GnomAD3 genomes

AF:

0.00423

AC:

643

AN:

152002

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0149

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000983

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:

0.0000441

Gnomad OTH

AF:

0.00382

GnomAD3 exomes

AF:

0.00113

AC:

284

AN:

250912

Hom.:

AF XY:

0.000671

AC XY:

AN XY:

135662

show subpopulations

Gnomad AFR exome

AF:

0.0156

Gnomad AMR exome

AF:

0.000579

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.000163

Gnomad SAS exome

AF:

0.0000653

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000176

Gnomad OTH exome

AF:

0.000652

GnomAD4 exome

AF:

0.000471

AC:

688

AN:

1460178

Hom.:

Cov.:

AF XY:

0.000410

AC XY:

298

AN XY:

726390

show subpopulations

Gnomad4 AFR exome

AF:

0.0177

Gnomad4 AMR exome

AF:

0.000738

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.000176

Gnomad4 SAS exome

AF:

0.0000348

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000540

Gnomad4 OTH exome

AF:

0.000730

GnomAD4 genome

AF:

0.00425

AC:

646

AN:

152120

Hom.:

Cov.:

AF XY:

0.00397

AC XY:

295

AN XY:

74360

show subpopulations

Gnomad4 AFR

AF:

0.0149

Gnomad4 AMR

AF:

0.000982

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000441

Gnomad4 OTH

AF:

0.00378

Alfa

AF:

0.000112

Hom.:

Bravo

AF:

0.00498

Asia WGS

AF:

0.000866

AC:

AN:

3478

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:7

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not specified

Benign:4

Benign, no assertion criteria provided	clinical testing	Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center	-	- -
Benign, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Jul 06, 2021	Variant summary: MYLK c.4289-9C>G alters a non-conserved nucleotide located close to a canonical splice site and therefore could affect mRNA splicing, leading to a significantly altered protein sequence. Several computational tools predict a significant impact on normal splicing: Four predict the variant slightly weakens a 3' acceptor site. However, these predictions have yet to be confirmed by functional studies. The variant allele was found at a frequency of 0.0011 in 250912 control chromosomes, predominantly at a frequency of 0.016 within the African or African-American subpopulation in the gnomAD database, including 4 homozygotes. The observed variant frequency within African or African-American control individuals in the gnomAD database is approximately 319.99 fold of the estimated maximal expected allele frequency for a pathogenic variant in MYLK causing Thoracic Aortic Aneurysms And Dissections phenotype (5e-05), strongly suggesting that the variant is a benign polymorphism found primarily in populations of African or African-American origin. To our knowledge, no occurrence of c.4289-9C>G in individuals affected with Thoracic Aortic Aneurysms And Dissections and no experimental evidence demonstrating its impact on protein function have been reported. Three clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as benign/likely benign. Based on the evidence outlined above, the variant was classified as benign. -
Benign, no assertion criteria provided	clinical testing	Genome Diagnostics Laboratory, Amsterdam University Medical Center	-	- -
Benign, criteria provided, single submitter	clinical testing	GeneDx	Mar 08, 2017	This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -

Aortic aneurysm, familial thoracic 7

Benign:2

Benign, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 25, 2024	- -
Likely benign, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Jan 12, 2018	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 and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

Familial thoracic aortic aneurysm and aortic dissection

Benign:1

Benign, criteria provided, single submitter

clinical testing

CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario

Nov 17, 2022

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.75

CADD

Benign

DANN

Benign

0.69

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.1

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Benign

0.00053

dbscSNV1_RF

Benign

0.068

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