rs876657894

Positions:

• chr12-110915783-G-A

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 3P and 4B. PM1 PP3 BS2

The NM_000432.4(MYL2):​c.101C>T​(p.Thr34Ile) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000743 in 1,614,050 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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T34N) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000075 (0 hom.)
• Consequence: MYL2 NM_000432.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 9.60

Genes affected

MYL2 (HGNC:7583): (myosin light chain 2) This gene encodes a major sarcomeric protein in mammalian striated muscle. The encoded protein plays a role in embryonic heart muscle structure and function, while phosphorylation of the encoded protein is involved in cardiac myosin cycling kinetics, torsion and function in adults. Mutations in this gene are associated with hypertrophic cardiomyopathy 10 and infant-onset myopathy. [provided by RefSeq, May 2022]

ACMG classification

Verdict is Likely_benign. Variant got -1 ACMG points.

• PM1: In a domain EF-hand 1 (size 35) in uniprot entity MLRV_HUMAN there are 11 pathogenic changes around while only 0 benign (100%) in NM_000432.4
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.835
• BS2: High AC in GnomAdExome4 at 11 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MYL2	NM_000432.4	c.101C>T	p.Thr34Ile	missense_variant	3/7	ENST00000228841.15
MYL2	NM_001406916.1	c.44C>T	p.Thr15Ile	missense_variant	3/7
MYL2	NM_001406745.1	c.94-1459C>T		intron_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MYL2	ENST00000228841.15	c.101C>T	p.Thr34Ile	missense_variant	3/7	1	NM_000432.4	P1
MYL2	ENST00000663220.1	c.44C>T	p.Thr15Ile	missense_variant	3/7
MYL2	ENST00000548438.1	c.94-1459C>T		intron_variant		3

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152212 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000752 AC: 11 AN: 1461838 Hom.: 0 Cov.: 31 AF XY: 0.00000550 AC XY: 4 AN XY: 727224

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: 0.00000989

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152212 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 74352

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Mar 30, 2021

The p.Thr34Ile variant in MYL2 has not been previously reported in individuals with cardiomyopathy and was absent from large population studies. Computational prediction tools and conservation analyses do not provide strong support for or against an impact to the protein. In summary, the clinical significance of this variant is uncertain. ACMG/AMP Criteria applied: PM2_Supporting. -

Cardiomyopathy Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Color Diagnostics, LLC DBA Color Health

Sep 26, 2019

This missense variant replaces threonine with isoleucine at codon 34 of the MYL2 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). Splice site prediction tools suggest that this variant may not impact RNA splicing. To our knowledge, functional studies have not been performed for this variant. This variant has not been reported in individuals affected with cardiovascular disorders in the literature. This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.96
CardioboostCm	Uncertain	0.83
BayesDel_addAF	Pathogenic	0.17	D
BayesDel_noAF	Uncertain	0.0
CADD	Pathogenic	28
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.79	D
Eigen	Uncertain	0.66
Eigen_PC	Pathogenic	0.68
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.95	D
M_CAP	Uncertain	0.095	D
MetaRNN	Pathogenic	0.84	D
MetaSVM	Uncertain	-0.23	T
MutationAssessor	Uncertain	2.1	M
MutationTaster	Benign	1.0	D;D
PrimateAI	Pathogenic	0.81	D
PROVEAN	Pathogenic	-4.4	D
REVEL	Uncertain	0.47
Sift	Uncertain	0.0050	D
Sift4G	Uncertain	0.033	D
Polyphen		0.71	P
Vest4		0.72
MutPred		0.45		Gain of catalytic residue at D37 (P = 0.0068);
MVP		0.91
MPC		0.99
ClinPred		0.99	D
GERP RS		5.1
Varity_R		0.89
gMVP		0.81

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: rs876657894; hg19: chr12-111353587;