X-77830901-G-C

Position:

• chrX-77830901-G-C

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_001367916.1(MAGT1):​c.902-6C>G variant causes a splice region, splice polypyrimidine tract, intron 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. 2/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 23)
• Consequence: MAGT1 NM_001367916.1 splice_region, splice_polypyrimidine_tract, intron
• Scores: Splicing: ADA: 0.002821
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.295

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_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.74).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MAGT1	NM_001367916.1	c.902-6C>G		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant		ENST00000618282.5	NP_001354845.1
MAGT1	NM_032121.5	c.998-6C>G		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant			NP_115497.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MAGT1	ENST00000618282.5	c.902-6C>G		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant		1	NM_001367916.1	ENSP00000480732	P1

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome Cov.: 17

GnomAD4 genome Cov.: 23

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

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

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Apr 17, 2020

This variant is not present in population databases (ExAC no frequency). 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 sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site, but this prediction has not been confirmed by published transcriptional studies. This variant has not been reported in the literature in individuals with MAGT1-related conditions. This sequence change falls in intron 8 of the MAGT1 gene. It does not directly change the encoded amino acid sequence of the MAGT1 protein. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.74
CADD	Benign	7.0
DANN	Benign	0.63

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.0028
dbscSNV1_RF	Benign	0.18
SpliceAI score (max)		0.22		Details are displayed if max score is > 0.2
DS_AL_spliceai		0.22		Position offset: -6

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-77086398;