X-154030917-T-C

Position:

• chrX-154030917-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP5

The NM_001110792.2(MECP2):​c.947A>G​(p.Lys316Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency: Genomes: not found (cov: 23)
• Consequence: MECP2 NM_001110792.2 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2 U:2
• Conservation: PhyloP100: 7.24

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 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant X-154030917-T-C is Pathogenic according to our data. Variant chrX-154030917-T-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 143743.We mark this variant Likely_pathogenic, oryginal submissions are: {Uncertain_significance=1, Pathogenic=1, Likely_pathogenic=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MECP2	NM_001110792.2	c.947A>G	p.Lys316Arg	missense_variant	3/3	ENST00000453960.7	NP_001104262.1
MECP2	NM_004992.4	c.911A>G	p.Lys304Arg	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.947A>G	p.Lys316Arg	missense_variant	3/3	1	NM_001110792.2	ENSP00000395535.2
MECP2	ENST00000303391.11	c.911A>G	p.Lys304Arg	missense_variant	4/4	1	NM_004992.4	ENSP00000301948.6

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome Cov.: 35

GnomAD4 genome Cov.: 23

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:2 Uncertain:2

Revision: criteria provided, conflicting classifications

Submissions by phenotype

not specified Uncertain:2

Uncertain significance, no assertion criteria provided	curation	RettBASE	Feb 15, 2011	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Genetic Services Laboratory, University of Chicago	Feb 08, 2013	- -

Rett syndrome Pathogenic:1

Likely pathogenic, criteria provided, single submitter

curation

Centre for Population Genomics, CPG

Mar 25, 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 likely pathogenic. At least the following criteria are met: Occurs in the well-characterized Transcriptional repression domain (TRD) of MECP2 (PM1). Another missense variant in the same codon has been classified as pathogenic (PM5) Computational prediction analysis tools suggests a deleterious impact (REVEL score>= 0.75) (PP3). This variant is absent from gnomAD (PM2_Supporting). -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Aug 08, 2023

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge; This variant is associated with the following publications: (PMID: 21831886) -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.63
BayesDel_addAF	Pathogenic	0.44	D
BayesDel_noAF	Pathogenic	0.39
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.57	D;.
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.95	D;D
M_CAP	Pathogenic	0.79	D
MetaRNN	Uncertain	0.70	D;D
MetaSVM	Uncertain	0.74	D
MutationAssessor	Uncertain	2.2	M;.
PrimateAI	Pathogenic	0.80	T
PROVEAN	Benign	-0.86	N;N
REVEL	Pathogenic	0.78
Sift	Pathogenic	0.0	D;D
Sift4G	Benign	0.51	T;T
Polyphen		0.99	D;D
Vest4		0.46
MutPred		0.63		Loss of methylation at K304 (P = 0.0039);.;
MVP		0.99
ClinPred		0.96	D
GERP RS		5.1
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.62
gMVP		0.95

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: rs267608550; hg19: chrX-153296368; COSMIC: COSV57652249; COSMIC: COSV57652249;