X-154031355-G-A

Position:

• chrX-154031355-G-A

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PM2 PP3_Strong PP5_Very_Strong

The NM_001110792.2(MECP2):​c.509C>T​(p.Thr170Met) variant causes a missense change involving the alteration of a 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 (★★).

• Frequency: Genomes: not found (cov: 23)
• Consequence: MECP2 NM_001110792.2 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:53 O:1
• Conservation: PhyloP100: 9.45

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 Pathogenic. Variant got 14 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.985
• PP5: Variant X-154031355-G-A is Pathogenic according to our data. Variant chrX-154031355-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 11811.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chrX-154031355-G-A is described in Lovd as [Pathogenic]. Variant chrX-154031355-G-A is described in Lovd as [Likely_pathogenic]. Variant chrX-154031355-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MECP2	NM_001110792.2	c.509C>T	p.Thr170Met	missense_variant	3/3	ENST00000453960.7	NP_001104262.1
MECP2	NM_004992.4	c.473C>T	p.Thr158Met	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.509C>T	p.Thr170Met	missense_variant	3/3	1	NM_001110792.2	ENSP00000395535
MECP2	ENST00000303391.11	c.473C>T	p.Thr158Met	missense_variant	4/4	1	NM_004992.4	ENSP00000301948	P1

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 23

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:53 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Rett syndrome Pathogenic:24 Other:1

Pathogenic, criteria provided, single submitter	clinical testing	Center of Genomic medicine, Geneva, University Hospital of Geneva	Jun 08, 2016	- -
Pathogenic, criteria provided, single submitter	curation	Centre for Population Genomics, CPG	Feb 28, 2024	This variant has been collected from RettBASE and curated to current modified ACMG/AMP criteria. Based on the classification scheme defined by the ClinGen Rett/Angelman-like Expert Panel for Rett/AS-like Disorders Specifications to the ACMG/AMP Variant Interpretation Guidelines VCEP 3.0, this variant is classified as pathogenic. At least the following criteria are met: This variant has been identified as a de novo occurrence in>=4 individuals with Rett syndrome without confirmation of paternity and maternity (PM6_very strong). PMID: 16225173 Has been observed in at least 5 individuals with phenotypes consistent with MECP2-related disease (PS4). PMID: 16473305 Occurs in the well-characterized Methyl-DNA binding (MDB) functional domain of MECP2 (PM1). Computational prediction analysis tools suggests a deleterious impact (REVEL score>= 0.75) (PP3). This variant is absent from gnomAD (PM2_Supporting). -
Pathogenic, no assertion criteria provided	clinical testing	Zotz-Klimas Genetics Lab, MVZ Zotz Klimas	Nov 02, 2023	- -
Pathogenic, criteria provided, single submitter	clinical testing	Lifecell International Pvt. Ltd	-	A Heterozygous Missense variant c.473C>T in Exon 4 of the MECP2 gene that results in the amino acid substitution p.Thr158Met was identified. The observed variant is novel in gnomAD exomes and genomes. The severity of the impact of this variant on the protein is medium, based on the effect of the protein and REVEL score . Rare Exome Variant Ensemble Learner (REVEL) is an ensembl method for predicting the pathogenicity of missense variants based on a combination of scores from 13 individual tools: MutPred, FATHMM v2.3, VEST 3.0, PolyPhen-2, SIFT, PROVEAN, MutationAssessor, MutationTaster, LRT, GERP++, SiPhy, phyloP, and phastCons. The REVEL score for an individual missense variant can range from 0 to 1, with higher scores reflecting greater likelihood that the variant is disease-causing. ClinVar has also classified this variant as Pathogenic [Variant ID : 11811]. This variant has previously been reported for Rett syndrome by Lee, Stephen Sung Jae, Mimi Wan, and Uta Francke., 2001. Experimental studies have shown that this missense change affects MECP2 protein function by Ballestar, Esteban, Timur M. Yusufzai, and Alan P. Wolffe., 2000. For these reasons this variant has been classified as Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Equipe Genetique des Anomalies du Developpement, Université de Bourgogne	Oct 04, 2023	- -
Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Oct 23, 2023	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Molecular Diagnostics Lab, Nemours Children's Health, Delaware	Jul 17, 2015	- -
Pathogenic, no assertion criteria provided	literature only	OMIM	Jul 01, 2007	- -
Pathogenic, criteria provided, single submitter	clinical testing	Center for Human Genetics, Inc, Center for Human Genetics, Inc	Nov 01, 2016	- -
not provided, no classification provided	literature only	GeneReviews	-	- -
Pathogenic, criteria provided, single submitter	clinical testing	Genetic Services Laboratory, University of Chicago	Feb 08, 2013	- -
Pathogenic, no assertion criteria provided	clinical testing	Clinical Laboratory Sciences Program (CLSP), King Saud bin Abdulaziz University for Health Sciences (KSAU-HS)	Apr 01, 2023	- -
Pathogenic, criteria provided, single submitter	clinical testing	3billion	Mar 22, 2022	Same or different nucleotide change resulting in same amino acid change has been previously reported as pathogenic/likely pathogenic with strong evidence (ClinVar ID: VCV000011811, PMID:10508514). A different missense change at the same codon has been reported as pathogenic/likely pathogenic with strong evidence (ClinVar ID: VCV000143590, PMID:11269512). The variant is located in a mutational hot spot and/or well-established functional domain in which established pathogenic variants have been reported. In silico tool predictions suggest damaging effect of the variant on gene or gene product (REVEL: 0.945>=0.6, 3CNET: 0.995>=0.75). It is not observed in the gnomAD v2.1.1 dataset. Therefore, this variant is classified as pathogenic according to the recommendation of ACMG/AMP guideline. -
Pathogenic, criteria provided, single submitter	clinical testing	Athena Diagnostics	Jul 25, 2012	- -
Pathogenic, criteria provided, single submitter	clinical testing	Neuberg Centre For Genomic Medicine, NCGM	-	The missense variant p.T158M in MECP2 (NM_004992.3) has been reported in multiple patients with Rett syndrome (Das DK et al; Brown K et al).It is the most common mutation in the Rett database.Functional studies have shown a damaging effect (Agarwal N et al). The variant has been submitted to ClinVar as Pathogenic. The p.T158M variant is novel (not in any individuals) in gnomAD Exomes and is novel (not in any individuals) in 1000 Genomes. The p.T158M missense variant is predicted to be damaging by both SIFT and PolyPhen2. The threonine residue at codon 158 of MECP2 is conserved in all mammalian species. The nucleotide c.473 in MECP2 is predicted conserved by GERP++ and PhyloP across 100 vertebrates. For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Genomic Research Center, Shahid Beheshti University of Medical Sciences	Aug 07, 2018	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Blueprint Genetics	Mar 09, 2018	- -
Pathogenic, no assertion criteria provided	clinical testing	Clinical Genetics Laboratory, University Hospital Schleswig-Holstein	Feb 01, 2022	- -
Pathogenic, criteria provided, single submitter	clinical testing	Institute for Genomic Statistics and Bioinformatics, University Hospital Bonn	-	- -
Pathogenic, criteria provided, single submitter	clinical testing	Institute of Human Genetics, University of Leipzig Medical Center	Aug 21, 2018	- -
Pathogenic, no assertion criteria provided	curation	RettBASE	Feb 26, 2014	- -
Pathogenic, no assertion criteria provided	clinical testing	Clinical Molecular Genetics Laboratory, Johns Hopkins All Children's Hospital	May 21, 2014	- -
Pathogenic, criteria provided, single submitter	clinical testing	Molecular Genetics Laboratory, Children's Mercy Hospital and Clinics	-	- -
Pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Sep 29, 2015	- -
Pathogenic, criteria provided, single submitter	clinical testing	Génétique des Maladies du Développement, Hospices Civils de Lyon	-	- -

not provided Pathogenic:14

Pathogenic, criteria provided, single submitter	clinical testing	Mayo Clinic Laboratories, Mayo Clinic	Mar 17, 2023	- -
Pathogenic, criteria provided, single submitter	clinical testing	ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories	Oct 14, 2023	The MECP2 c.473C>T; p.Thr158Met variant (rs28934906), is reported in the literature in multiple individuals affected with classical Rett syndrome (see link to RettBASE and references therein). This variant is reported as pathogenic by multiple laboratories in ClinVar (Variation ID: 11811), and is absent from general population databases (1000 Genomes Project, Exome Variant Server, and Genome Aggregation Database), indicating it is not a common polymorphism. The threonine at codon 158 is highly conserved, and computational analyses (SIFT, PolyPhen-2) predict that this variant is deleterious. Based on available information, the p.Thr158Met variant is considered to be pathogenic. References: Link to RettBASE (http://mecp2.chw.edu.au/cgi-bin/mecp2/search/process-search.cgi) -
Pathogenic, criteria provided, single submitter	clinical testing	Clinical Genetics and Genomics, Karolinska University Hospital	Feb 22, 2016	- -
Pathogenic, no assertion criteria provided	clinical testing	Genomic Diagnostic Laboratory, Division of Genomic Diagnostics, Children's Hospital of Philadelphia	Apr 03, 2015	- -
Pathogenic, no assertion criteria provided	clinical testing	Genetics and Genomic Medicine Centre, NeuroGen Healthcare, NeuroGen Healthcare	Mar 18, 2022	- -
Pathogenic, no assertion criteria provided	clinical testing	Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+	-	- -
Pathogenic, no assertion criteria provided	clinical testing	Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center	-	- -
Pathogenic, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Oct 01, 2023	MECP2: PS2, PM1, PM2, PM5, PS3:Moderate, PP3, PS4:Supporting -
Pathogenic, criteria provided, single submitter	clinical testing	Revvity Omics, Revvity	Feb 12, 2021	- -
Pathogenic, no assertion criteria provided	clinical testing	Genome Diagnostics Laboratory, University Medical Center Utrecht	-	- -
Pathogenic, criteria provided, single submitter	clinical testing	Institute of Medical Genetics and Applied Genomics, University Hospital Tübingen	Oct 23, 2020	- -
Pathogenic, criteria provided, single submitter	clinical testing	Center for Pediatric Genomic Medicine, Children's Mercy Hospital and Clinics	Oct 22, 2015	- -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Jul 30, 2021	Recurrent missense substitution that accounts for 9-12% of MECP2 pathogenic variants and has been identified in females with both classic and atypical Rett syndrome (Percy et al., 2007; Neul et al., 2008; Bao et al., 2013; RettBASE); Also identified in males with severe neonatal-onset encephalopathy and in females who did not meet clinical criteria for Rett syndrome but had overlapping clinical features, including pervasive developmental disorder or clinical features suggestive of Angelman syndrome (Suter et al., 2014; Kleefstra et al., 2005; Villard et al., 2000); In vitro functional studies indicate that T158M impairs normal protein function (Yusufzai et al., 2000; Kudo et al., 2003; Agarwal et al., 2011; Lyst et al., 2013; Sheikh et al., 2016); Not observed at significant frequency in large population cohorts (Lek et al., 2016); This variant is associated with the following publications: (PMID: 31031587, 12030010, 12843318, 21831886, 11071498, 28920956, 31535341, 31095231, 30945278, 30868116, 29655203, 30564305, 26175308, 28135719, 17236109, 17881312, 16077729, 25533962, 23921973, 12719401, 26418480, 26647311, 26795593, 23770565, 11058114, 10508514, 18337588, 18174548, 23421866, 14560307, 24511209, 23270700, 19442733, 19217433, 11738866, 11392517, 11738879, 10852707, 27929079) -
Pathogenic, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Oct 02, 2015	- -

Severe neonatal-onset encephalopathy with microcephaly Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 15, 2024	This sequence change replaces threonine, which is neutral and polar, with methionine, which is neutral and non-polar, at codon 158 of the MECP2 protein (p.Thr158Met). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with Rett syndrome and is considered one of the most common causes of the condition (PMID: 10508514, 18337588, 23421866, 26647311; RettBASE). In at least one individual the variant was observed to be de novo. ClinVar contains an entry for this variant (Variation ID: 11811). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt MECP2 protein function with a positive predictive value of 95%. Experimental studies have shown that this missense change affects MECP2 function (PMID: 10852707, 11058114, 11738866, 12843318, 21831886, 26647311). For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, no assertion criteria provided	curation	RettBASE	Feb 26, 2014	- -
Pathogenic, no assertion criteria provided	literature only	OMIM	Jul 01, 2007	- -

Rett syndrome;C0796222:X-linked intellectual disability-psychosis-macroorchidism syndrome;C1845336:Autism, susceptibility to, X-linked 3;C1846058:Syndromic X-linked intellectual disability Lubs type;C1968556:Severe neonatal-onset encephalopathy with microcephaly Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	Center for Genomics, Ann and Robert H. Lurie Children's Hospital of Chicago	Mar 30, 2021	MECP2 NM_004992.3 exon 4 p.Thr158Met (c.473C>T): This variant is one of the most common mutations associated with Rett syndrome, identified in several individuals (n>100) including males, with Rett syndrome. This variant has been identified to segregate with disease and has also been reported to occur as de novo (Selected publications: Amir 1999 PMID: 10508514, Villard 2000 PMID:11071498, Neul 2008 PMID:18337588, Bao 2013 PMID:23421866, RettBASE http://mecp2.chw.edu.au/). This variant is not present in large control databases. This variant is present in ClinVar, with multiple labs classifying this variant as pathogenic (Variation ID:11811). Evolutionary conservation and computational predictive tools suggest that this variant may impact the protein. In addition, in vivo functional studies support a deleterious effect of this variant, suggesting impaired binding stability and selectivity for methylated DNA (Yusufzai 2000 PMID:11058114, Bao 2013 PMID:23421866). Furthermore, this variant occurs in exon 4; the vast majority of pathogenic variants are identified in exon 4 which encodes for the methyl binding domain and transcription repression domain. Loss of function has been established for this gene, but missense variants have been described as pathogenic as well. (Philippe 2006 16473305). In summary, this variant is classified as pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Fulgent Genetics, Fulgent Genetics	Oct 31, 2018	- -
Pathogenic, no assertion criteria provided	clinical testing	Service de Génétique Moléculaire, Hôpital Robert Debré	-	- -

MECP2-related disorder Pathogenic:2

Pathogenic, no assertion criteria provided	clinical testing	PreventionGenetics, part of Exact Sciences	May 06, 2024	The MECP2 c.473C>T variant is predicted to result in the amino acid substitution p.Thr158Met. This is the most commonly reported pathogenic variant responsible for Rett Syndrome, with over 40 studies cited in the Human Gene Mutation database, and several examples of de novo occurrence (see for example, Amir et al. 1999. PubMed ID: 10508514; Knight. 2013. PubMed ID: 23270700; Guerrini and Parrini. 2012. PubMed ID: 22998673). Functional analysis has indicated that this variant impairs DNA binding affinity (Kucukkal et al. 2015. PubMed ID: 26418480; Yusufzai and Wolffe. 2000. PubMed ID: 11058114). This variant has not been reported in a large population database (http://gnomad.broadinstitute.org), indicating this variant is absent or extremely rare in general populations. This variant is interpreted as pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Dec 21, 2021	The MECP2 c.509C>T p.(Thr170Met) missense variant, also known as c.473C>T p.(Thr158Met), has been identified in individuals with a phenotype consistent with MECP2-related disorders and is reported as one of the most commonly occurring variants in affected individuals (Aron et al. 2019; Xiong et al. 2019; Wen et al. 2020). At least two probands in the literature were confirmed to have de novo inheritance (Xiong et al. 2019). This variant is not observed in version 2.1.1 or version 3.1.2 of the Genome Aggregation Database. The c.509C>T variant disrupts hydrogen bonding in a critical region of the C-terminal end of the methyl-DNA binding region (MDB), a well-established functional domain, which leads to compromised binding to methylated DNA and affects stability (Brown et al. 2016). This variant was identified in a de novo state in the proband. The c.509C>T variant is highly conserved through evolution. Based on the available evidence, the c.509C>T p.(Thr170Met) variant is classified as pathogenic for MECP2-related disorders. -

Neurodevelopmental delay Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Centre de Biologie Pathologie Génétique, Centre Hospitalier Universitaire de Lille

-

- -

Syndromic X-linked intellectual disability Lubs type Pathogenic:1

Pathogenic, criteria provided, single submitter

research

Center for Genomic Medicine, King Faisal Specialist Hospital and Research Center

Mar 14, 2024

- -

Inborn genetic diseases Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 07, 2020

The c.473C>T (p.T158M) alteration is located in exon 4 (coding exon 3) of the MECP2 gene. This alteration results from a C to T substitution at nucleotide position 473, causing the threonine (T) at amino acid position 158 to be replaced by a methionine (M). Based on data from the Genome Aggregation Database (gnomAD), the MECP2 c.473C>T alteration was not observed, with coverage at this position. The MECP2 c.473C>T (p.T158M) alteration is one of the most common pathogenic variants in MECP2, occurring at a CpG hotspot (Amir, 1999). This alteration has been identified in female patients with both classical Rett syndrome as well as atypical Rett syndrome; more mildly affected individuals have also been described with this alteration (Amir, 1999; Buyse, 2000; Huppke, 2000; Auranen, 2001; Bao, 2013; Suter, 2014). Functional analysis demonstrated that the p.T158M alteration moderately affects MeCP2's ability to bind to methylated DNA and impair selectivity for methylated DNA (Ballestar, 2000; Yusufzai, 2000). The p.T158M alteration is predicted to be deleterious by in silico analysis. Based on the available evidence, this alteration is classified as pathogenic. -

Angelman syndrome Pathogenic:1

Pathogenic, no assertion criteria provided

curation

RettBASE

Feb 26, 2014

- -

Abnormality of the nervous system Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Kariminejad - Najmabadi Pathology & Genetics Center

Jul 10, 2021

- -

Autism, susceptibility to, X-linked 3 Pathogenic:1

Pathogenic, no assertion criteria provided

curation

RettBASE

Feb 26, 2014

- -

X-linked intellectual disability-psychosis-macroorchidism syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Mendelics

May 04, 2022

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.68	D
BayesDel_noAF	Pathogenic	0.74
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.98	D;.;D;T;T
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.98	D;D;D;D;D
M_CAP	Pathogenic	0.99	D
MetaRNN	Pathogenic	0.98	D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Benign	1.8	L;.;.;.;.
MutationTaster	Benign	1.0	A;A;A
PrimateAI	Pathogenic	0.87	D
PROVEAN	Uncertain	-4.3	D;D;.;.;.
REVEL	Pathogenic	0.94
Sift	Uncertain	0.0010	D;D;.;.;.
Sift4G	Uncertain	0.0080	D;D;.;D;D
Polyphen		1.0	D;D;.;.;.
Vest4		0.75
MutPred		0.88		Loss of phosphorylation at T158 (P = 0.0197);.;Loss of phosphorylation at T158 (P = 0.0197);.;.;
MVP		1.0
ClinPred		1.0	D
GERP RS		5.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.91
gMVP		0.81

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

Publications

LitVar

Other links and lift over

dbSNP: rs28934906; hg19: chrX-153296806; COSMIC: COSV57651729; COSMIC: COSV57651729;