rs1554102961

Positions:

• chr5-137875863-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The ENST00000239926.9(MYOT):​c.391G>T​(p.Ala131Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 15/19 in silico tools predict a benign 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. A131E) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: MYOT ENST00000239926.9 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.45

Genes affected

MYOT (HGNC:12399): (myotilin) This gene encodes a cystoskeletal protein which plays a significant role in the stability of thin filaments during muscle contraction. This protein binds F-actin, crosslinks actin filaments, and prevents latrunculin A-induced filament disassembly. Mutations in this gene have been associated with limb-girdle muscular dystrophy and myofibrillar myopathies. Several alternatively spliced transcript variants of this gene have been described, but the full-length nature of some of these variants has not been determined.[provided by RefSeq, Oct 2008]

PKD2L2-DT (HGNC:55557): (PKD2L2 divergent transcript)

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.08107141).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MYOT	NM_006790.3	c.391G>T	p.Ala131Ser	missense_variant	3/10	ENST00000239926.9	NP_006781.1
PKD2L2-DT	XR_948815.3	n.302+12297C>A		intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MYOT	ENST00000239926.9	c.391G>T	p.Ala131Ser	missense_variant	3/10	1	NM_006790.3	ENSP00000239926	P1
PKD2L2-DT	ENST00000514616.6	n.319+12297C>A		intron_variant, non_coding_transcript_variant		5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Myofibrillar myopathy 3 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

May 31, 2017

In summary, this variant has uncertain impact on MYOT function. The available evidence is currently insufficient to determine its role 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 (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This variant has not been reported in the literature in individuals with a MYOT-related disease. This variant is not present in population databases (ExAC no frequency). This sequence change replaces alanine with serine at codon 131 of the MYOT protein (p.Ala131Ser). The alanine residue is moderately conserved and there is a moderate physicochemical difference between alanine and serine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.078
BayesDel_addAF	Benign	-0.15	T
BayesDel_noAF	Benign	-0.45
CADD	Benign	17
DANN	Benign	0.95
Eigen	Benign	-0.39
Eigen_PC	Benign	-0.19
FATHMM_MKL	Uncertain	0.88	D
LIST_S2	Benign	0.66	T;T
M_CAP	Benign	0.019	T
MetaRNN	Benign	0.081	T;T
MetaSVM	Benign	-1.0	T
MutationTaster	Benign	0.97	D;N;N
PrimateAI	Benign	0.31	T
PROVEAN	Benign	-0.39	N;N
REVEL	Benign	0.077
Sift	Benign	0.13	T;T
Sift4G	Benign	0.35	T;T
Vest4		0.15
MutPred		0.096		Gain of glycosylation at A131 (P = 0.0362);.;
MVP		0.81
MPC		0.16
ClinPred		0.19	T
GERP RS		3.7
gMVP		0.19

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.060		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: rs1554102961; hg19: chr5-137211552;