2-77518425-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_001134745.3(LRRTM4):c.1444C>A(p.Gln482Lys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,076 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: LRRTM4 NM_001134745.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 10.0

Genes affected

LRRTM4 (HGNC:19411): (leucine rich repeat transmembrane neuronal 4) Predicted to enable heparan sulfate proteoglycan binding activity. Predicted to be involved in regulation of synapse assembly. Predicted to act upstream of or within AMPA glutamate receptor clustering; positive regulation of synapse assembly; and regulation of presynaptic membrane organization. Predicted to be located in postsynaptic membrane. Predicted to be part of AMPA glutamate receptor complex. Predicted to be active in extracellular matrix; extracellular space; and glutamatergic synapse. Predicted to be integral component of postsynaptic density membrane. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
LRRTM4	NM_001134745.3	c.1444C>A	p.Gln482Lys	missense_variant	3/4	ENST00000409884.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
LRRTM4	ENST00000409884.6	c.1444C>A	p.Gln482Lys	missense_variant	3/4	1	NM_001134745.3	P4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461076 Hom.: 0 Cov.: 34 AF XY: 0.00000138 AC XY: 1 AN XY: 726830

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.0000187

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ExAC AF: 0.00000828 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Dec 21, 2023

The c.1444C>A (p.Q482K) alteration is located in exon 3 (coding exon 2) of the LRRTM4 gene. This alteration results from a C to A substitution at nucleotide position 1444, causing the glutamine (Q) at amino acid position 482 to be replaced by a lysine (K). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.62
BayesDel_addAF	Pathogenic	0.19	D
BayesDel_noAF	Uncertain	0.030
Cadd	Pathogenic	29
Dann	Uncertain	0.99
DEOGEN2	Benign	0.022	T;T;T;.;T
Eigen	Pathogenic	0.95
Eigen_PC	Pathogenic	0.93
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Pathogenic	0.98	D;.;D;D;D
M_CAP	Benign	0.076	D
MetaRNN	Uncertain	0.51	D;D;D;D;D
MetaSVM	Uncertain	0.24	D
MutationTaster	Benign	1.0	D;D;D;D;D
PrimateAI	Pathogenic	0.80	T
PROVEAN	Benign	-2.0	N;N;N;N;N
REVEL	Uncertain	0.54
Sift	Uncertain	0.0020	D;D;D;D;D
Sift4G	Uncertain	0.0060	D;D;D;D;D
Polyphen		1.0, 1.0	.;D;D;D;D
Vest4		0.61
MutPred		0.49		.;Gain of methylation at Q482 (P = 0.0037);Gain of methylation at Q482 (P = 0.0037);Gain of methylation at Q482 (P = 0.0037);.;
MVP		0.54
MPC		1.7
ClinPred		0.91	D
GERP RS		5.7
Varity_R		0.61
gMVP		0.80

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: rs751743214; hg19: chr2-77745551;