rs1060500985

Positions:

• chr20-31821648-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_033118.4(MYLK2):​c.683T>C​(p.Ile228Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,740 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 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. I228I) has been classified as Benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: MYLK2 NM_033118.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.328

Genes affected

MYLK2 (HGNC:16243): (myosin light chain kinase 2) This gene encodes a myosin light chain kinase, a calcium/calmodulin dependent enzyme, that is exclusively expressed in adult skeletal muscle. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.18108544).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MYLK2	NM_033118.4	c.683T>C	p.Ile228Thr	missense_variant	4/13	ENST00000375985.5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MYLK2	ENST00000375985.5	c.683T>C	p.Ile228Thr	missense_variant	4/13	1	NM_033118.4	P1
MYLK2	ENST00000375994.6	c.683T>C	p.Ile228Thr	missense_variant	3/12	1		P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461740 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 727154

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hypertrophic cardiomyopathy 1 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jun 13, 2016

Algorithms developed to predict the effect of missense changes on protein structure and function output the following: (SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0"). The threonine amino acid residue is also found in multiple mammalian species, suggesting that this missense change does not adversely affect protein function. These predictions have not been confirmed by published functional studies. In summary, this variant is a novel missense change that is not predicted to affect protein function. There is no indication that it causes disease, but the available evidence is currently insufficient to prove that conclusively. Therefore, it has been classified as a Variant of Uncertain Significance. This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a MYLK2-related disease. This sequence change replaces isoleucine with threonine at codon 228 of the MYLK2 protein (p.Ile228Thr). The isoleucine residue is moderately conserved and there is a moderate physicochemical difference between isoleucine and threonine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.079
BayesDel_addAF	Benign	-0.13	T
BayesDel_noAF	Benign	-0.43
CADD	Benign	15
DANN	Uncertain	0.99
DEOGEN2	Benign	0.24	T;T
Eigen	Benign	-0.38
Eigen_PC	Benign	-0.38
FATHMM_MKL	Benign	0.38	N
M_CAP	Benign	0.016	T
MetaRNN	Benign	0.18	T;T
MetaSVM	Benign	-0.94	T
MutationAssessor	Uncertain	2.3	M;M
MutationTaster	Benign	1.0	N;N
PrimateAI	Benign	0.46	T
PROVEAN	Benign	-0.76	N;N
REVEL	Benign	0.054
Sift	Benign	0.050	D;D
Sift4G	Benign	0.32	T;T
Polyphen		0.72	P;P
Vest4		0.15
MutPred		0.35		Gain of phosphorylation at I228 (P = 0.0073);Gain of phosphorylation at I228 (P = 0.0073);
MVP		0.73
MPC		0.11
ClinPred		0.16	T
GERP RS		2.7
Varity_R		0.046
gMVP		0.13

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.040		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: rs1060500985; hg19: chr20-30409451;