X-154030864-G-C

Variant names:

• chrX-154030864-G-C
• rs61751449
• NM_001110792.2:c.1000C>G

Variant summary

Our verdict is Pathogenic. The variant received 13 ACMG points: 14P and 1B. PM1 PM2 PM5 PP5_Very_Strong BP4

The NM_001110792.2(MECP2):​c.1000C>G​(p.Pro334Ala) 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 benign 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. P334S) has been classified 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:3 U:1
• Conservation: PhyloP100: 1.86
• Publications: 18 publications found

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]

MECP2 Gene-Disease associations (from GenCC):

• chromosome Xq28 duplication syndrome

  Inheritance: XL Classification: DEFINITIVE Submitted by: G2P
• Rett syndrome

  Inheritance: XL Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), Ambry Genetics, ClinGen, G2P
• severe neonatal-onset encephalopathy with microcephaly

  Inheritance: XL Classification: DEFINITIVE, SUPPORTIVE Submitted by: G2P, Orphanet
• syndromic X-linked intellectual disability Lubs type

  Inheritance: XL Classification: DEFINITIVE Submitted by: G2P
• atypical Rett syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• non-syndromic X-linked intellectual disability

  Inheritance: XL Classification: SUPPORTIVE Submitted by: Orphanet
• X-linked intellectual disability-psychosis-macroorchidism syndrome

  Inheritance: XL Classification: SUPPORTIVE Submitted by: Orphanet
• systemic lupus erythematosus

  Inheritance: Unknown Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 13 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 3 benign, 10 uncertain in NM_001110792.2
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chrX-154030864-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 11843.
• PP5: Variant X-154030864-G-C is Pathogenic according to our data. Variant chrX-154030864-G-C is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 143753.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BP4: Computational evidence support a benign effect (MetaRNN=0.4071775). . Strength limited to SUPPORTING due to the PP5.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MECP2	NM_001110792.2	c.1000C>G	p.Pro334Ala	missense_variant	Exon 3 of 3	ENST00000453960.7	NP_001104262.1
MECP2	NM_004992.4	c.964C>G	p.Pro322Ala	missense_variant	Exon 4 of 4	ENST00000303391.11	NP_004983.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MECP2	ENST00000453960.7	c.1000C>G	p.Pro334Ala	missense_variant	Exon 3 of 3	1	NM_001110792.2	ENSP00000395535.2
MECP2	ENST00000303391.11	c.964C>G	p.Pro322Ala	missense_variant	Exon 4 of 4	1	NM_004992.4	ENSP00000301948.6

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome Cov.: 36

GnomAD4 genome Cov.: 23

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:3 Uncertain:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Rett syndrome Pathogenic:1 Uncertain:1

May 18, 2012

RettBASE

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: curation

- -

Jan 09, 2024

Centre for Population Genomics, CPG

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: curation

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 likely pathogenic. At least the following criteria are met: This variant is absent from gnomAD (PM2_Supporting). This variant has been identified as a de novo occurrence in at least one individual with Rett syndrome without confirmation of paternity and maternity (PM6). PMID: 11462237, PMID: 16225173 Has been observed in at least 5 individuals with phenotypes consistent with MECP2-related disease (PS4). PMID: 16473305, PMID: 11462237, PMID: 18174559, ClinVar database(Variation ID: 143753) -

Severe neonatal-onset encephalopathy with microcephaly Pathogenic:1

Nov 27, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces proline, which is neutral and non-polar, with alanine, which is neutral and non-polar, at codon 322 of the MECP2 protein (p.Pro322Ala). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individuals with Rett syndrome (PMID: 10814719, 11462237, 15737703, 16225173). This variant is also known as 1038C>G. ClinVar contains an entry for this variant (Variation ID: 143753). 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 not expected to disrupt MECP2 protein function with a negative predictive value of 95%. This variant disrupts the p.Pro322 amino acid residue in MECP2. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 15526954, 17089071, 29718204). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

not provided Pathogenic:1

May 01, 2022

CeGaT Center for Human Genetics Tuebingen

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

MECP2: PS2, PM2, PM5, PS4:Moderate -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.23
BayesDel_addAF	Benign	-0.023	T
BayesDel_noAF	Pathogenic	0.15
CADD	Benign	21
DANN	Uncertain	0.98
DEOGEN2	Benign	0.10	T
FATHMM_MKL	Benign	0.65	D
LIST_S2	Benign	0.26	T
M_CAP	Pathogenic	0.86	D
MetaRNN	Benign	0.41	T
PhyloP100		1.9
Sift4G	Benign	0.28	T
Vest4		0.27
MVP		0.97
ClinPred		0.40	T
GERP RS		5.1
Varity_R		0.20
Mutation Taster		=11/89	disease causing

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

Other links and lift over

dbSNP: rs61751449; hg19: chrX-153296315;