20-31819581-A-G

Variant names:

• chr20-31819581-A-G
• NM_033118.4:c.1A>G

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PVS1_Supporting PM2

The NM_033118.4(MYLK2):​c.1A>G​(p.Met1?) variant causes a start lost change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000143 in 1,399,244 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 (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: MYLK2 NM_033118.4 start_lost
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.86

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 3 ACMG points.

• PVS1: Start lost variant, no pathogenic variants between lost start and next in-frame start position. Next in-frame start position is after 181 codons. Genomic position: 31821506. Lost 0.302 part of the original CDS.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MYLK2	NM_033118.4	c.1A>G	p.Met1?	start_lost	Exon 2 of 13	ENST00000375985.5	NP_149109.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MYLK2	ENST00000375985.5	c.1A>G	p.Met1?	start_lost	Exon 2 of 13	1	NM_033118.4	ENSP00000365152.4
MYLK2	ENST00000375994.6	c.1A>G	p.Met1?	start_lost	Exon 1 of 12	1		ENSP00000365162.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000143 AC: 2 AN: 1399244 Hom.: 0 Cov.: 31 AF XY: 0.00000145 AC XY: 1 AN XY: 690102

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: 0.0000126

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 9.27e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Sep 03, 2024

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Has not been previously published as pathogenic or benign to our knowledge; Not observed at significant frequency in large population cohorts (gnomAD); Initiation codon variant in a gene for which loss-of-function is not a known mechanism of disease -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.23	D
BayesDel_noAF	Uncertain	0.090
CADD	Benign	23
DANN	Uncertain	0.99
DEOGEN2	Benign	0.26	T;T
Eigen	Uncertain	0.20
Eigen_PC	Benign	0.19
FATHMM_MKL	Uncertain	0.87	D
LIST_S2	Uncertain	0.90	.;D
M_CAP	Pathogenic	0.74	D
MetaRNN	Pathogenic	0.99	D;D
MetaSVM	Benign	-0.46	T
PROVEAN	Benign	-0.74	N;N
REVEL	Uncertain	0.45
Sift	Pathogenic	0.0	D;D
Sift4G	Benign	0.33	T;T
Polyphen		0.71	P;P
Vest4		0.65
MutPred		1.0		Gain of catalytic residue at E4 (P = 0.1784);Gain of catalytic residue at E4 (P = 0.1784);
MVP		0.67
ClinPred		0.89	D
GERP RS		3.5
Varity_R		0.82
gMVP		0.036

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr20-30407384;