chrX-154031179-G-C

Variant names:

• chrX-154031179-G-C
• rs786205894
• NM_001110792.2:c.685C>G

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 6P and 1B. PM1 PM2 PM5 BP4

The NM_001110792.2(MECP2):​c.685C>G​(p.Pro229Ala) variant causes a missense change. The variant allele was found at a frequency of 0.000000911 in 1,098,262 control chromosomes in the GnomAD database, with no homozygous occurrence. There are 1 hemizygotes in GnomAD. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P229L) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 23)
  • Exomes 𝑓: 9.1e-7 (0 hom. 1 hem.)
• Consequence: MECP2 NM_001110792.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.58
• Publications: 0 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: Uncertain_significance. The variant received 5 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 6 benign, 8 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-154031178-G-A is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 236302.Status of the report is reviewed_by_expert_panel, 3 stars.
• BP4: Computational evidence support a benign effect (MetaRNN=0.35758585).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MECP2	NM_001110792.2	c.685C>G	p.Pro229Ala	missense_variant	Exon 3 of 3	ENST00000453960.7	NP_001104262.1
MECP2	NM_004992.4	c.649C>G	p.Pro217Ala	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.685C>G	p.Pro229Ala	missense_variant	Exon 3 of 3	1	NM_001110792.2	ENSP00000395535.2
MECP2	ENST00000303391.11	c.649C>G	p.Pro217Ala	missense_variant	Exon 4 of 4	1	NM_004992.4	ENSP00000301948.6

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome AF: 9.11e-7 AC: 1 AN: 1098262 Hom.: 0 Cov.: 35 AF XY: 0.00000275 AC XY: 1 AN XY: 363616

African (AFR) AF: 0.0000379 AC: 1 AN: 26403

American (AMR) AF: 0.00 AC: 0 AN: 35207

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 19386

East Asian (EAS) AF: 0.00 AC: 0 AN: 30206

South Asian (SAS) AF: 0.00 AC: 0 AN: 54147

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 40533

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 4137

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 842145

Other (OTH) AF: 0.00 AC: 0 AN: 46098

GnomAD4 genome Cov.: 23

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Apr 15, 2025

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis indicates 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	Benign	0.076
BayesDel_addAF	Uncertain	0.15	D
BayesDel_noAF	Uncertain	-0.020
CADD	Benign	20
DANN	Uncertain	0.98
DEOGEN2	Uncertain	0.42	T;.;T;T
FATHMM_MKL	Uncertain	0.89	D
LIST_S2	Uncertain	0.95	D;D;D;D
M_CAP	Pathogenic	0.69	D
MetaRNN	Benign	0.36	T;T;T;T
MetaSVM	Uncertain	0.23	D
MutationAssessor	Uncertain	2.1	M;.;.;.
PhyloP100		3.6
PrimateAI	Uncertain	0.63	T
PROVEAN	Benign	-1.6	N;N;.;.
REVEL	Uncertain	0.46
Sift	Uncertain	0.014	D;D;.;.
Sift4G	Uncertain	0.032	D;T;.;T
Vest4		0.22
ClinPred		0.65	D
GERP RS		5.5
Varity_R		0.29
gMVP		0.68
Mutation Taster		=38/62	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: rs786205894; hg19: chrX-153296630;