chrX-120431363-A-G

Position:

• chrX-120431363-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_002294.3(LAMP2):​c.1193T>C​(p.Ile398Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000912 in 1,096,622 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 (★★).

• Frequency:
  • Genomes: not found (cov: 24)
  • Exomes 𝑓: 9.1e-7 (0 hom. 0 hem.)
• Consequence: LAMP2 NM_002294.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 8.51

Genes affected

LAMP2 (HGNC:6501): (lysosomal associated membrane protein 2) The protein encoded by this gene is a member of a family of membrane glycoproteins. This glycoprotein provides selectins with carbohydrate ligands. It may play a role in tumor cell metastasis. It may also function in the protection, maintenance, and adhesion of the lysosome. Alternative splicing of this gene results in multiple transcript variants encoding distinct proteins. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.801

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
LAMP2	NM_002294.3	c.1193T>C	p.Ile398Thr	missense_variant	9/9	ENST00000200639.9	NP_002285.1
LAMP2	NM_001122606.1	c.1094-2737T>C		intron_variant			NP_001116078.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
LAMP2	ENST00000200639.9	c.1193T>C	p.Ile398Thr	missense_variant	9/9	1	NM_002294.3	ENSP00000200639.4

Frequencies

GnomAD3 genomes Cov.: 24

GnomAD4 exome AF: 9.12e-7 AC: 1 AN: 1096622 Hom.: 0 Cov.: 29 AF XY: 0.00 AC XY: 0 AN XY: 362176

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: 0.00000119

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 24

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Jul 31, 2013

The Ile398Thr variant in LAMP2 has not been reported in individuals with cardiom yopathy or in large population studies. Computational analyses (biochemical amin o acid properties, conservation, AlignGVGD, PolyPhen2, and SIFT) suggest that th is variant may impact the protein, though this information is not predictive eno ugh to determine pathogenicity. Of note, pathogenic missense variants are very r are in the LAMP2 gene (most disease causing variants cause a truncated or absent protein).Additional information is needed to fully assess the clinical signific ance of this variant. -

Danon disease Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 20, 2022

This sequence change replaces isoleucine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 398 of the LAMP2 protein (p.Ile398Thr). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with LAMP2-related conditions. ClinVar contains an entry for this variant (Variation ID: 179100). 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 LAMP2 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

Dec 15, 2023

Has not been previously published as pathogenic or benign to our knowledge; Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.13
CardioboostCm	Benign	0.013
BayesDel_addAF	Pathogenic	0.20	D
BayesDel_noAF	Uncertain	0.050
CADD	Uncertain	26
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.46	T
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Benign	0.60	T
M_CAP	Pathogenic	0.35	D
MetaRNN	Pathogenic	0.80	D
MetaSVM	Uncertain	-0.17	T
MutationAssessor	Pathogenic	3.3	M
PROVEAN	Pathogenic	-4.5	D
REVEL	Uncertain	0.56
Sift	Uncertain	0.0010	D
Sift4G	Uncertain	0.0030	D
Polyphen		1.0	D
Vest4		0.64
MVP		0.82
ClinPred		0.98	D
GERP RS		5.8
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.7
Varity_R		0.87

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: rs727504625; hg19: chrX-119565218;