X-77830888-A-T

Position:

• chrX-77830888-A-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PVS1_Moderate PM2 PP5_Moderate

The NM_001367916.1(MAGT1):​c.909T>A​(p.Cys303Ter) 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 (★).

• Frequency: Genomes: not found (cov: 22)
• Consequence: MAGT1 NM_001367916.1 stop_gained
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 1.50

Genes affected

MAGT1 (HGNC:28880): (magnesium transporter 1) This gene encodes a ubiquitously expressed magnesium cation transporter protein that localizes to the cell membrane. This protein also associates with N-oligosaccharyl transferase and therefore may have a role in N-glycosylation. Mutations in this gene cause a form of X-linked intellectual disability (XLID). This gene may have multiple in-frame translation initiation sites, one of which would encode a shorter protein with an N-terminus containing a signal peptide at amino acids 1-29. [provided by RefSeq, Jul 2017]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most 50 bp of the penultimate exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.0982 CDS is truncated, and there are 0 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant X-77830888-A-T is Pathogenic according to our data. Variant chrX-77830888-A-T is described in ClinVar as [Pathogenic]. Clinvar id is 1458559.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MAGT1	NM_001367916.1	c.909T>A	p.Cys303Ter	stop_gained	9/10	ENST00000618282.5	NP_001354845.1
MAGT1	NM_032121.5	c.1005T>A	p.Cys335Ter	stop_gained	9/10		NP_115497.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MAGT1	ENST00000618282.5	c.909T>A	p.Cys303Ter	stop_gained	9/10	1	NM_001367916.1	ENSP00000480732	P1

Frequencies

GnomAD3 genomes Cov.: 22

GnomAD4 exome Cov.: 20

GnomAD4 genome Cov.: 22

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

X-linked immunodeficiency with magnesium defect, Epstein-Barr virus infection and neoplasia Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 09, 2022

For these reasons, this variant has been classified as Pathogenic. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. ClinVar contains an entry for this variant (Variation ID: 1458559). This variant has not been reported in the literature in individuals affected with MAGT1-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change creates a premature translational stop signal (p.Cys335*) in the MAGT1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in MAGT1 are known to be pathogenic (PMID: 24550228). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.66	D
BayesDel_noAF	Pathogenic	0.27
CADD	Pathogenic	34
DANN	Uncertain	0.98
FATHMM_MKL	Benign	0.53	D
MutationTaster	Benign	1.0	A
Vest4		0.90
GERP RS		-1.2

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

No publications associated with this variant yet.

Other links and lift over

hg19: chrX-77086385;