rs886039133

chr16-15823345-T-A

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM2 PP2 PP3_Moderate

The NM_002474.3(MYH11):c.412A>T(p.Ile138Phe) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000031 in 1,614,064 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. I138T) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: MYH11 NM_002474.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:4
• Conservation: PhyloP100: 7.97

Genes affected

MYH11 (HGNC:7569): (myosin heavy chain 11) The protein encoded by this gene is a smooth muscle myosin belonging to the myosin heavy chain family. The gene product is a subunit of a hexameric protein that consists of two heavy chain subunits and two pairs of non-identical light chain subunits. It functions as a major contractile protein, converting chemical energy into mechanical energy through the hydrolysis of ATP. A chromosomal rearrangement involving this gene is associated with acute myeloid leukemia of the M4Eo subtype. Mutations in this gene are associated with visceral myopathy, megacystis-microcolon-intestinal hypoperistalsis syndrome 2, and familial thoracic aortic aneurysm 4. [provided by RefSeq, May 2022]

ACMG classification

Verdict is Uncertain_significance. Variant got 5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant where missense usually causes diseases, MYH11
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.845

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MYH11	NM_002474.3	c.412A>T	p.Ile138Phe	missense_variant	3/41	ENST00000300036.6
MYH11	NM_001040113.2	c.412A>T	p.Ile138Phe	missense_variant	3/43	ENST00000452625.7
MYH11	NM_001040114.2	c.412A>T	p.Ile138Phe	missense_variant	3/42
MYH11	NM_022844.3	c.412A>T	p.Ile138Phe	missense_variant	3/42

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MYH11	ENST00000300036.6	c.412A>T	p.Ile138Phe	missense_variant	3/41	1	NM_002474.3	P3
MYH11	ENST00000452625.7	c.412A>T	p.Ile138Phe	missense_variant	3/43	1	NM_001040113.2

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152172 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: 0.00000274 AC: 4 AN: 1461892 Hom.: 0 Cov.: 34 AF XY: 0.00000138 AC XY: 1 AN XY: 727246

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000447

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: 0.00000180

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152172 Hom.: 0 Cov.: 33 AF XY: 0.0000135 AC XY: 1 AN XY: 74332

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:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Familial thoracic aortic aneurysm and aortic dissection Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	All of Us Research Program, National Institutes of Health	Dec 13, 2023	This missense variant replaces isoleucine with phenylalanine at codon 138 of the MYH11 protein. Computational prediction suggests that this variant may have deleterious impact on protein structure and function (internally defined REVEL score threshold >= 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with MYH11-related 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. -
Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Sep 22, 2015	The p.I138F variant (also known as c.412A>T), located in coding exon 2 of the MYH11 gene, results from an A to T substitution at nucleotide position 412. The isoleucine at codon 138 is replaced by phenylalanine, an amino acid with highly similar properties. This variant was not reported in population based cohorts in the following databases: Database of Single Nucleotide Polymorphisms (dbSNP), NHLBI Exome Sequencing Project (ESP), and 1000 Genomes Project. In the ESP, this variant was not observed in 6497 samples (12994 alleles) with coverage at this position. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this variant remains unclear. -

Aortic aneurysm, familial thoracic 4 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Oct 23, 2023

This sequence change replaces isoleucine, which is neutral and non-polar, with phenylalanine, which is neutral and non-polar, at codon 138 of the MYH11 protein (p.Ile138Phe). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with MYH11-related conditions. ClinVar contains an entry for this variant (Variation ID: 264360). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt MYH11 protein function with a negative predictive value of 95%. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Aortic aneurysm, familial thoracic 4;C5543466:Visceral myopathy 2;C5543476:Megacystis-microcolon-intestinal hypoperistalsis syndrome 2 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Oct 12, 2021

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.83
BayesDel_addAF	Pathogenic	0.31	D
BayesDel_noAF	Pathogenic	0.21
Cadd	Pathogenic	27
Dann	Uncertain	0.99
Eigen	Pathogenic	0.78
Eigen_PC	Pathogenic	0.76
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.97	D;D;D;D
M_CAP	Uncertain	0.13	D
MetaRNN	Pathogenic	0.85	D;D;D;D
MetaSVM	Uncertain	0.087	D
MutationAssessor	Benign	1.8	L;L;L;L
MutationTaster	Benign	1.0	D;D;D;D;D
PrimateAI	Pathogenic	0.82	D
PROVEAN	Uncertain	-3.5	D;D;.;D
REVEL	Pathogenic	0.85
Sift	Uncertain	0.0010	D;D;.;D
Sift4G	Uncertain	0.0020	D;D;D;D
Polyphen		0.99	.;.;.;D
Vest4		0.82
MutPred		0.67		Gain of methylation at K137 (P = 0.0748);Gain of methylation at K137 (P = 0.0748);Gain of methylation at K137 (P = 0.0748);Gain of methylation at K137 (P = 0.0748);
MVP		0.88
MPC		2.2
ClinPred		0.99	D
GERP RS		5.6
Varity_R		0.66
gMVP		0.85

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: rs886039133; hg19: chr16-15917202;