chr20-31819601-A-C

Variant names:

• chr20-31819601-A-C
• rs754853086
• NM_033118.4:c.21A>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_033118.4(MYLK2):​c.21A>C​(p.Ala7Ala) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000143 in 1,399,288 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. A7A) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: MYLK2 NM_033118.4 synonymous
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: 0.572
• Publications: 0 publications found

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]

MYLK2 Gene-Disease associations (from GenCC):

• hypertrophic cardiomyopathy 1

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
• hypertrophic cardiomyopathy

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

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=-0.58).
• BP6: Variant 20-31819601-A-C is Benign according to our data. Variant chr20-31819601-A-C is described in ClinVar as Likely_benign. ClinVar VariationId is 3650727.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP7: Synonymous conserved (PhyloP=0.572 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MYLK2	NM_033118.4	c.21A>C	p.Ala7Ala	synonymous_variant	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.21A>C	p.Ala7Ala	synonymous_variant	Exon 2 of 13	1	NM_033118.4	ENSP00000365152.4
MYLK2	ENST00000375994.6	c.21A>C	p.Ala7Ala	synonymous_variant	Exon 1 of 12	1		ENSP00000365162.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000143 AC: 2 AN: 1399288 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 690132

African (AFR) AF: 0.00 AC: 0 AN: 31598

American (AMR) AF: 0.00 AC: 0 AN: 35706

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25180

East Asian (EAS) AF: 0.00 AC: 0 AN: 35738

South Asian (SAS) AF: 0.00 AC: 0 AN: 79236

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 49148

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5698

European-Non Finnish (NFE) AF: 0.00000185 AC: 2 AN: 1078980

Other (OTH) AF: 0.00 AC: 0 AN: 58004

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hypertrophic cardiomyopathy 1 Benign:1

Apr 24, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.58
CADD	Benign	7.9
DANN	Benign	0.75
PhyloP100		0.57
PromoterAI		0.042	Neutral

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

Other links and lift over

dbSNP: rs754853086; hg19: chr20-30407404;