NM_000252.3:c.27T>G

Variant names:

• chrX-150592641-T-G
• NM_000252.3:c.27T>G

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_000252.3(MTM1):​c.27T>G​(p.Tyr9*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★). Synonymous variant affecting the same amino acid position (i.e. Y9Y) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 23)
• Consequence: MTM1 NM_000252.3 stop_gained
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 0.719
• Publications: 0 publications found

Genes affected

MTM1 (HGNC:7448): (myotubularin 1) This gene encodes a dual-specificity phosphatase that acts on both phosphotyrosine and phosphoserine. It is required for muscle cell differentiation and mutations in this gene have been identified as being responsible for X-linked myotubular myopathy. [provided by RefSeq, Jul 2008]

MTM1 Gene-Disease associations (from GenCC):

• X-linked myotubular myopathy

  Inheritance: XL Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Orphanet, ClinGen, G2P, Myriad Women’s Health, Ambry Genetics

ACMG classification

Our verdict: Pathogenic. The variant received 12 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant located near the start codon (<100nt), not predicted to undergo nonsense mediated mRNA decay. There are 215 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant X-150592641-T-G is Pathogenic according to our data. Variant chrX-150592641-T-G is described in ClinVar as Pathogenic. ClinVar VariationId is 2753250.Status of the report is criteria_provided_single_submitter, 1 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000252.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MTM1	NM_000252.3	MANE Select	c.27T>G	p.Tyr9*	stop_gained	Exon 2 of 15	NP_000243.1	Q13496-1
	MTM1	NM_001376908.1		c.27T>G	p.Tyr9*	stop_gained	Exon 2 of 15	NP_001363837.1	Q13496-1
	MTM1	NM_001376906.1		c.27T>G	p.Tyr9*	stop_gained	Exon 2 of 15	NP_001363835.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MTM1	ENST00000370396.7	TSL:1 MANE Select	c.27T>G	p.Tyr9*	stop_gained	Exon 2 of 15	ENSP00000359423.3	Q13496-1
	MTM1	ENST00000689314.1		c.27T>G	p.Tyr9*	stop_gained	Exon 2 of 16	ENSP00000510607.1	A0A8I5KZ76
	MTM1	ENST00000866458.1		c.27T>G	p.Tyr9*	stop_gained	Exon 2 of 16	ENSP00000536517.1

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome Cov.: 26

GnomAD4 genome Cov.: 23

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
1	-	-	Severe X-linked myotubular myopathy (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.74	D
BayesDel_noAF	Pathogenic	0.56
CADD	Pathogenic	33
DANN	Uncertain	1.0
FATHMM_MKL	Benign	0.75	D
PhyloP100		0.72
Vest4		0.90
GERP RS		3.3
Mutation Taster		=0/200	disease causing (fs/PTC)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.040		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

hg19: chrX-149761103; COSMIC: COSV60333621;