rs752021743

Positions:

• chr3-123722264-G-A

Variant summary

Our verdict is Benign. Variant got -13 ACMG points: 0P and 13B. BP4_Strong BP6_Very_Strong BP7

The NM_053025.4(MYLK):​c.1668C>T​(p.Tyr556=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000446 in 1,569,442 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

• Frequency:
  • Genomes: 𝑓 0.000046 (0 hom., cov: 34)
  • Exomes 𝑓: 0.000044 (0 hom.)
• Consequence: MYLK NM_053025.4 synonymous
• Clinical Significance: Likely benign criteria provided, multiple submitters, no conflicts B:4
• Conservation: PhyloP100: -1.60

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]

ACMG classification

Verdict is Benign. Variant got -13 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.76).
• BP6: Variant 3-123722264-G-A is Benign according to our data. Variant chr3-123722264-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 262275.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BP7: Synonymous conserved (PhyloP=-1.6 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MYLK	NM_053025.4	c.1668C>T	p.Tyr556=	synonymous_variant	13/34	ENST00000360304.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MYLK	ENST00000360304.8	c.1668C>T	p.Tyr556=	synonymous_variant	13/34	5	NM_053025.4	P4

Frequencies

GnomAD3 genomes AF: 0.0000460 AC: 7 AN: 152222 Hom.: 0 Cov.: 34

Gnomad AFR AF: 0.0000965

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000413

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000440 AC: 8 AN: 181726 Hom.: 0 AF XY: 0.0000723 AC XY: 7 AN XY: 96774

Gnomad AFR exome AF: 0.0000926

Gnomad AMR exome AF: 0.0000358

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.000208

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000133

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000445 AC: 63 AN: 1417220 Hom.: 0 Cov.: 41 AF XY: 0.0000500 AC XY: 35 AN XY: 700476

Gnomad4 AFR exome AF: 0.0000306

Gnomad4 AMR exome AF: 0.0000259

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000537

Gnomad4 SAS exome AF: 0.0000872

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000441

Gnomad4 OTH exome AF: 0.0000682

GnomAD4 genome AF: 0.0000460 AC: 7 AN: 152222 Hom.: 0 Cov.: 34 AF XY: 0.0000672 AC XY: 5 AN XY: 74360

Gnomad4 AFR AF: 0.0000965

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000413

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000329 Hom.: 0

Bravo AF: 0.0000491

ClinVar

Significance: Likely benign

Submissions summary: Benign:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Aortic aneurysm, familial thoracic 7 Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 20, 2023

- -

not specified Benign:1

Likely benign, criteria provided, single submitter

clinical testing

PreventionGenetics, part of Exact Sciences

-

- -

Familial thoracic aortic aneurysm and aortic dissection Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 07, 2022

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. -

not provided Benign:1

Likely benign, criteria provided, single submitter

clinical testing

GeneDx

Feb 11, 2021

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.76
CADD	Benign	0.078
DANN	Benign	0.35

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

LitVar

Other links and lift over

dbSNP: rs752021743; hg19: chr3-123441111;