X-153862682-G-T

Position:

• chrX-153862682-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_001278116.2(L1CAM):​c.3755C>A​(p.Pro1252His) variant causes a missense change. 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 Uncertain significance (★).

• Frequency: Genomes: not found (cov: 24)
• Consequence: L1CAM NM_001278116.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 5.49

Genes affected

L1CAM (HGNC:6470): (L1 cell adhesion molecule) The protein encoded by this gene is an axonal glycoprotein belonging to the immunoglobulin supergene family. The ectodomain, consisting of several immunoglobulin-like domains and fibronectin-like repeats (type III), is linked via a single transmembrane sequence to a conserved cytoplasmic domain. This cell adhesion molecule plays an important role in nervous system development, including neuronal migration and differentiation. Mutations in the gene cause X-linked neurological syndromes known as CRASH (corpus callosum hypoplasia, retardation, aphasia, spastic paraplegia and hydrocephalus). Alternative splicing of this gene results in multiple transcript variants, some of which include an alternate exon that is considered to be specific to neurons. [provided by RefSeq, May 2013]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.4219868).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
L1CAM	NM_001278116.2	c.3755C>A	p.Pro1252His	missense_variant	29/29	ENST00000370060.7	NP_001265045.1
L1CAM	NM_000425.5	c.3755C>A	p.Pro1252His	missense_variant	28/28		NP_000416.1
L1CAM	NM_024003.3	c.3743C>A	p.Pro1248His	missense_variant	27/27		NP_076493.1
L1CAM	NM_001143963.2	c.3728C>A	p.Pro1243His	missense_variant	26/26		NP_001137435.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
L1CAM	ENST00000370060.7	c.3755C>A	p.Pro1252His	missense_variant	29/29	5	NM_001278116.2	ENSP00000359077.1

Frequencies

GnomAD3 genomes Cov.: 24

GnomAD4 exome Cov.: 29

GnomAD4 genome Cov.: 24

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

MASA syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Victorian Clinical Genetics Services, Murdoch Childrens Research Institute

Feb 02, 2022

Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as VUS-3B. Following criteria are met: 0102 - Loss of function is a known mechanism of disease in this gene and is associated with partial agenesis of corpus callosum (MIM#304100), CRASH syndrome (MIM#303350), Hydrocephalus due to aqueductal stenosis (MIM#307000), Hydrocephalus with congenital idiopathic intestinal pseudoobstruction (MIM#307000), Hydrocephalus with Hirschsprung disease (MIM#307000), MASA syndrome (MIM#303350). (I) 0109 - This gene is associated with X-linked recessive disease. (I) 0115 - Variants in this gene are known to have variable expressivity. This gene is well known for its intra- and interfamilial variability in individuals with the same variant (OMIM). (I) 0200 - Variant is predicted to result in a missense amino acid change from proline to histidine. (I) 0253 - This variant is hemizygous. (I) 0301 - Variant is absent from gnomAD (both v2 and v3). (SP) 0502 - Missense variant with conflicting in silico predictions and uninformative conservation. (I) 0604 - Variant is not located in an established domain, motif, hotspot or informative constraint region. (I) 0710 - Another missense variant comparable to the one identified in this case has inconclusive previous evidence for pathogenicity. An alternative change to a serine has been reported once as VUS (ClinVar). (I) 0807 - This variant has no previous evidence of pathogenicity. (I) 0905 - No published segregation evidence has been identified for this variant. (I) 1007 - No published functional evidence has been identified for this variant. (I) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.22
BayesDel_addAF	Uncertain	0.13	D
BayesDel_noAF	Uncertain	-0.050
CADD	Benign	23
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.59	.;D;.;T;.
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Benign	0.82	T;T;.;T;T
M_CAP	Pathogenic	0.45	D
MetaRNN	Benign	0.42	T;T;T;T;T
MetaSVM	Uncertain	0.25	D
MutationAssessor	Benign	1.7	.;L;.;.;.
PrimateAI	Uncertain	0.55	T
PROVEAN	Uncertain	-2.8	D;D;D;N;D
REVEL	Benign	0.19
Sift	Pathogenic	0.0	D;D;D;D;D
Sift4G	Uncertain	0.0030	D;D;D;D;D
Polyphen		0.056, 1.0	.;B;.;.;D
Vest4		0.28
MutPred		0.32		.;Loss of phosphorylation at S1248 (P = 0.1387);.;.;.;
MVP		0.88
MPC		1.6
ClinPred		0.99	D
GERP RS		4.7
Varity_R		0.70
gMVP		0.66

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

No publications associated with this variant yet.

Other links and lift over

hg19: chrX-153128137;