rs55760507

Variant names:

• chr3-123739964-G-A
• rs55760507
• NM_053025.4:c.411C>T

Your query was ambiguous. Multiple possible variants found:

• chr3-123739964-G-A
• chr3-123739964-G-C

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 2P and 7B. PM2 BP4_Strong BP6_Moderate BP7

The NM_053025.4(MYLK):​c.411C>T​(p.Ser137Ser) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,622 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 (★). Synonymous variant affecting the same amino acid position (i.e. S137S) has been classified as Benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: MYLK NM_053025.4 synonymous
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: 2.08
• Publications: 0 publications found

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
• megacystis-microcolon-intestinal hypoperistalsis syndrome 1

  Inheritance: AR Classification: STRONG Submitted by: G2P
• familial thoracic aortic aneurysm and aortic dissection

  Inheritance: Unknown, AD Classification: STRONG, SUPPORTIVE Submitted by: ClinGen, Orphanet
• 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

ACMG classification

Our verdict: Likely_benign. The variant received -5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.5).
• BP6: Variant 3-123739964-G-A is Benign according to our data. Variant chr3-123739964-G-A is described in ClinVar as Likely_benign. ClinVar VariationId is 2762929.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP7: Synonymous conserved (PhyloP=2.08 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_053025.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MYLK	NM_053025.4	MANE Select	c.411C>T	p.Ser137Ser	synonymous	Exon 6 of 34	NP_444253.3
	MYLK	NM_053027.4		c.411C>T	p.Ser137Ser	synonymous	Exon 6 of 33	NP_444255.3
	MYLK	NM_053026.4		c.411C>T	p.Ser137Ser	synonymous	Exon 6 of 33	NP_444254.3

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MYLK	ENST00000360304.8	TSL:5 MANE Select	c.411C>T	p.Ser137Ser	synonymous	Exon 6 of 34	ENSP00000353452.3	Q15746-1
	MYLK	ENST00000464489.5	TSL:1	n.203C>T		non_coding_transcript_exon	Exon 5 of 33	ENSP00000417798.1	F8WBL7
	MYLK	ENST00000687848.1		c.441C>T	p.Ser147Ser	synonymous	Exon 4 of 32	ENSP00000508761.1	A0A8I5KU53

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461622 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727112

⚠️ 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: 33478

American (AMR) AF: 0.00 AC: 0 AN: 44720

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26130

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86218

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53412

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111820

Other (OTH) AF: 0.00 AC: 0 AN: 60380

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.00000000770867), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 33

ClinVar

ClinVar submissions

Significance: Likely benign

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	-	1	Aortic aneurysm, familial thoracic 7 (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.16
BayesDel_noAF	Benign	-0.50
CADD	Benign	8.2
DANN	Benign	0.87
PhyloP100		2.1

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

Other links and lift over

dbSNP: rs55760507; hg19: chr3-123458811;