rs1557137821

chrX-154032334-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM1 PM2 PP3

The NM_001110792.2(MECP2):c.286C>T(p.Arg96Trp) variant causes a missense change. The variant allele was found at a frequency of 0.00000182 in 1,097,327 control chromosomes in the GnomAD database, with no homozygous occurrence. There are no hemizygote samples in GnomAD. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R96Q) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 24)
  • Exomes 𝑓: 0.0000018 (0 hom. 0 hem.)
• Consequence: MECP2 NM_001110792.2 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 6.03

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 Uncertain_significance. Variant got 5 ACMG points.

• PM1: In a domain MBD (size 72) in uniprot entity MECP2_HUMAN there are 59 pathogenic changes around while only 4 benign (94%) in NM_001110792.2
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.759

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MECP2	NM_001110792.2	c.286C>T	p.Arg96Trp	missense_variant	2/3	ENST00000453960.7
MECP2	NM_004992.4	c.250C>T	p.Arg84Trp	missense_variant	3/4	ENST00000303391.11

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MECP2	ENST00000453960.7	c.286C>T	p.Arg96Trp	missense_variant	2/3	1	NM_001110792.2
MECP2	ENST00000303391.11	c.250C>T	p.Arg84Trp	missense_variant	3/4	1	NM_004992.4	P1

Frequencies

GnomAD3 genomes Cov.: 24

GnomAD4 exome AF: 0.00000182 AC: 2 AN: 1097327 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 362753

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000238

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 24

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Severe neonatal-onset encephalopathy with microcephaly Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jun 27, 2022

This sequence change replaces arginine, which is basic and polar, with tryptophan, which is neutral and slightly polar, at codon 84 of the MECP2 protein (p.Arg84Trp). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with MECP2-related conditions. ClinVar contains an entry for this variant (Variation ID: 536586). 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. 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. -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Feb 24, 2021

Not observed in large population cohorts (Lek et al., 2016); In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect; Has not been previously published as pathogenic or benign to our knowledge -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.61	D
BayesDel_noAF	Pathogenic	0.64
Cadd	Pathogenic	27
Dann	Pathogenic	1.0
DEOGEN2	Pathogenic	0.85	D;.;T;T;T;T;T
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Pathogenic	0.99	D;D;D;D;D;D;D
M_CAP	Pathogenic	0.55	D
MetaRNN	Pathogenic	0.76	D;D;D;D;D;D;D
MetaSVM	Pathogenic	0.94	D
MutationAssessor	Benign	0.90	L;.;.;.;.;.;.
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Pathogenic	0.89	D
PROVEAN	Uncertain	-3.7	D;D;.;.;.;.;.
REVEL	Pathogenic	0.69
Sift	Pathogenic	0.0	D;D;.;.;.;.;.
Sift4G	Uncertain	0.027	D;D;D;D;.;D;D
Polyphen		1.0	D;D;.;.;.;.;.
Vest4		0.81
MutPred		0.30		Gain of ubiquitination at K82 (P = 0.0222);.;Gain of ubiquitination at K82 (P = 0.0222);.;Gain of ubiquitination at K82 (P = 0.0222);.;.;
MVP		1.0
ClinPred		0.99	D
GERP RS		5.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.72
gMVP		0.94

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs1557137821; hg19: chrX-153297785; COSMIC: COSV57657855; COSMIC: COSV57657855;