rs1555459204

Positions:

• chr16-15837981-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_002474.3(MYH11):​c.272C>T​(p.Ala91Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,461,892 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: 31)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: MYH11 NM_002474.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 10.0

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 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.902

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MYH11	NM_002474.3	c.272C>T	p.Ala91Val	missense_variant	2/41	ENST00000300036.6	NP_002465.1
MYH11	NM_001040113.2	c.272C>T	p.Ala91Val	missense_variant	2/43	ENST00000452625.7	NP_001035202.1
MYH11	NM_001040114.2	c.272C>T	p.Ala91Val	missense_variant	2/42		NP_001035203.1
MYH11	NM_022844.3	c.272C>T	p.Ala91Val	missense_variant	2/42		NP_074035.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MYH11	ENST00000300036.6	c.272C>T	p.Ala91Val	missense_variant	2/41	1	NM_002474.3	ENSP00000300036.5
MYH11	ENST00000452625.7	c.272C>T	p.Ala91Val	missense_variant	2/43	1	NM_001040113.2	ENSP00000407821.2

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1461892 Hom.: 0 Cov.: 32 AF XY: 0.00000413 AC XY: 3 AN XY: 727246

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000270

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Familial thoracic aortic aneurysm and aortic dissection Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Color Diagnostics, LLC DBA Color Health

Jan 05, 2021

This missense variant replaces alanine with valine at codon 91 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 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. -

Aortic aneurysm, familial thoracic 4 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 12, 2017

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. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). This variant has not been reported in the literature in individuals with MYH11-related disease. This variant is not present in population databases (ExAC no frequency). This sequence change replaces alanine with valine at codon 91 of the MYH11 protein (p.Ala91Val). The alanine residue is highly conserved and there is a small physicochemical difference between alanine and valine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.78
BayesDel_addAF	Pathogenic	0.32	D
BayesDel_noAF	Pathogenic	0.22
CADD	Pathogenic	31
DANN	Pathogenic	1.0
DEOGEN2	Uncertain	0.79	.;.;.;D
Eigen	Pathogenic	0.83
Eigen_PC	Pathogenic	0.85
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.96	D;D;D;D
M_CAP	Uncertain	0.10	D
MetaRNN	Pathogenic	0.90	D;D;D;D
MetaSVM	Uncertain	-0.018	T
MutationAssessor	Benign	1.6	L;L;L;L
PrimateAI	Pathogenic	0.87	D
PROVEAN	Uncertain	-3.3	D;D;.;D
REVEL	Pathogenic	0.71
Sift	Uncertain	0.0010	D;D;.;D
Sift4G	Uncertain	0.028	D;D;D;D
Polyphen		1.0	.;.;.;D
Vest4		0.88
MutPred		0.72		Loss of ubiquitination at K86 (P = 0.0863);Loss of ubiquitination at K86 (P = 0.0863);Loss of ubiquitination at K86 (P = 0.0863);Loss of ubiquitination at K86 (P = 0.0863);
MVP		0.90
MPC		1.8
ClinPred		0.99	D
GERP RS		5.7
Varity_R		0.67
gMVP		0.65

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: rs1555459204; hg19: chr16-15931838; COSMIC: COSV55569204;