chrX-154030367-T-G

Position:

• chrX-154030367-T-G

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PM4 PP5_Moderate

The NM_001110792.2(MECP2):​c.1497A>C​(p.Ter499Cysext*?) variant causes a stop lost change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Likely pathogenic (★).

• Frequency: Genomes: not found (cov: 23)
• Consequence: MECP2 NM_001110792.2 stop_lost
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1 U:1
• Conservation: PhyloP100: 6.23

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 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM4: Stoplost variant in NM_001110792.2 Downstream stopcodon found after 8 codons.
• PP5: Variant X-154030367-T-G is Pathogenic according to our data. Variant chrX-154030367-T-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 143489.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MECP2	NM_001110792.2	c.1497A>C	p.Ter499Cysext*?	stop_lost	3/3	ENST00000453960.7	NP_001104262.1
MECP2	NM_004992.4	c.1461A>C	p.Ter487Cysext*?	stop_lost	4/4	ENST00000303391.11	NP_004983.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MECP2	ENST00000453960.7	c.1497A>C	p.Ter499Cysext*?	stop_lost	3/3	1	NM_001110792.2	ENSP00000395535.2
MECP2	ENST00000303391.11	c.1461A>C	p.Ter487Cysext*?	stop_lost	4/4	1	NM_004992.4	ENSP00000301948.6
MECP2	ENST00000628176	c.*833A>C		3_prime_UTR_variant	5/5	3		ENSP00000486978.1

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 23

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1 Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Rett syndrome Pathogenic:1 Uncertain:1

Uncertain significance, no assertion criteria provided	curation	RettBASE	Apr 10, 2002	- -
Likely pathogenic, criteria provided, single submitter	curation	Centre for Population Genomics, CPG	Aug 14, 2023	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 2.0, this variant is classified as Likely pathogenic. At least the following criteria are met: Protein length changes due to in-frame deletions/insertions in a non-repeat region or stop-loss variants (PM4_strong). This variant is absent from gnomAD (PM2_Supporting). This variant has been identified as a de novo occurrence in an individual with Rett syndrome without confirmation of paternity and maternity (PM6, PMID 10814719). At least one patient with this variant has been reported in an individual with a clinical phenotype suggestive of Rett syndrome (PP4, PMID: 10814719). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Uncertain	0.049	T
BayesDel_noAF	Benign	-0.17
CADD	Benign	17
DANN	Benign	0.69
FATHMM_MKL	Uncertain	0.97	D
Vest4		0.38
GERP RS		5.8

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: rs267608642; hg19: chrX-153295818;