X-154031065-G-C

Position:

• chrX-154031065-G-C

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM1 PM2 PP3 PP5_Moderate

The ENST00000453960.7(MECP2):​c.799C>G​(p.Arg267Gly) 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 pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R267P) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 23)
• Consequence: MECP2 ENST00000453960.7 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 2.35

Genes affected

MECP2 (HGNC:6990): (methyl-CpG binding protein 2) DNA methylation is the major modification of eukaryotic genomes and plays an essential role in mammalian development. Human proteins MECP2, MBD1, MBD2, MBD3, and MBD4 comprise a family of nuclear proteins related by the presence in each of a methyl-CpG binding domain (MBD). Each of these proteins, with the exception of MBD3, is capable of binding specifically to methylated DNA. MECP2, MBD1 and MBD2 can also repress transcription from methylated gene promoters. In contrast to other MBD family members, MECP2 is X-linked and subject to X inactivation. MECP2 is dispensible in stem cells, but is essential for embryonic development. MECP2 gene mutations are the cause of most cases of Rett syndrome, a progressive neurologic developmental disorder and one of the most common causes of cognitive disability in females. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Oct 2015]

ACMG classification

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

• PM1: In a DNA_binding_region A.T hook 2 (size 12) in uniprot entity MECP2_HUMAN there are 6 pathogenic changes around while only 2 benign (75%) in ENST00000453960.7
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.805
• PP5: Variant X-154031065-G-C is Pathogenic according to our data. Variant chrX-154031065-G-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 978959.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chrX-154031065-G-C is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MECP2	NM_001110792.2	c.799C>G	p.Arg267Gly	missense_variant	3/3	ENST00000453960.7	NP_001104262.1
MECP2	NM_004992.4	c.763C>G	p.Arg255Gly	missense_variant	4/4	ENST00000303391.11	NP_004983.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MECP2	ENST00000453960.7	c.799C>G	p.Arg267Gly	missense_variant	3/3	1	NM_001110792.2	ENSP00000395535
MECP2	ENST00000303391.11	c.763C>G	p.Arg255Gly	missense_variant	4/4	1	NM_004992.4	ENSP00000301948	P1

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome Cov.: 35

GnomAD4 genome Cov.: 23

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Intellectual disability Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Diagnostic Laboratory, Strasbourg University Hospital

Apr 20, 2020

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Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.89
BayesDel_addAF	Pathogenic	0.56	D
BayesDel_noAF	Pathogenic	0.57
CADD	Benign	22
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.82	D;.;T;T
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Pathogenic	0.98	D;D;T;D
M_CAP	Pathogenic	0.94	D
MetaRNN	Pathogenic	0.78	D;D;D;D
MetaSVM	Pathogenic	0.83	D
MutationAssessor	Uncertain	2.3	M;.;.;.
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Pathogenic	0.81	D
PROVEAN	Uncertain	-2.6	D;D;.;.
REVEL	Pathogenic	0.72
Sift	Pathogenic	0.0	D;D;.;.
Sift4G	Benign	0.11	T;D;.;D
Polyphen		0.99	D;D;.;.
Vest4		0.60
MutPred		0.30		Gain of relative solvent accessibility (P = 0.0479);.;Gain of relative solvent accessibility (P = 0.0479);.;
MVP		1.0
ClinPred		0.98	D
GERP RS		3.5
Varity_R		0.80
gMVP		0.91

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: rs61749721; hg19: chrX-153296516;