12-1831312-A-C

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_001039029.3(LRTM2):c.445A>C(p.Ile149Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,488 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: LRTM2 NM_001039029.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.358

Genes affected

LRTM2 (HGNC:32443): (leucine rich repeats and transmembrane domains 2) Predicted to enable Roundabout binding activity and heparin binding activity. Predicted to be involved in axon guidance and negative chemotaxis. Predicted to act upstream of or within positive regulation of synapse assembly. Predicted to be integral component of membrane. [provided by Alliance of Genome Resources, Apr 2022]

CACNA2D4 (HGNC:20202): (calcium voltage-gated channel auxiliary subunit alpha2delta 4) This gene encodes a member of the alpha-2/delta subunit family, a protein in the voltage-dependent calcium channel complex. Calcium channels mediate the influx of calcium ions into the cell upon membrane polarization and consist of a complex of alpha-1, alpha-2/delta, beta, and gamma subunits in a 1:1:1:1 ratio. Various versions of each of these subunits exist, either expressed from similar genes or the result of alternative splicing. Research on a highly similar protein in rabbit suggests the protein described in this record is cleaved into alpha-2 and delta subunits. Alternate transcriptional splice variants of this gene have been observed but have not been thoroughly characterized. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.105867535).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
LRTM2	NM_001039029.3	c.445A>C	p.Ile149Leu	missense_variant	4/5	ENST00000299194.6
CACNA2D4	NM_172364.5	c.2551+9427T>G		intron_variant		ENST00000382722.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
LRTM2	ENST00000299194.6	c.445A>C	p.Ile149Leu	missense_variant	4/5	2	NM_001039029.3	P1
CACNA2D4	ENST00000382722.10	c.2551+9427T>G		intron_variant		1	NM_172364.5	P2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461488 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 727082

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: 0.00000180

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ESP6500AA AF: 0.00 AC: 0

ESP6500EA AF: 0.000116 AC: 1

ExAC AF: 0.00000824 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

Jun 06, 2022

The c.445A>C (p.I149L) alteration is located in exon 4 (coding exon 2) of the LRTM2 gene. This alteration results from a A to C substitution at nucleotide position 445, causing the isoleucine (I) at amino acid position 149 to be replaced by a leucine (L). 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	Benign	0.092
BayesDel_addAF	Benign	-0.21	T
BayesDel_noAF	Benign	-0.54
Cadd	Benign	11
Dann	Benign	0.69
DEOGEN2	Benign	0.010	T;T;T
Eigen	Benign	-0.70
Eigen_PC	Benign	-0.54
FATHMM_MKL	Benign	0.068	N
M_CAP	Benign	0.014	T
MetaRNN	Benign	0.11	T;T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	-0.26	N;N;N
MutationTaster	Benign	1.0	D;D;D;D;D;D;D;D;D
PrimateAI	Uncertain	0.60	T
PROVEAN	Benign	0.24	N;N;N
REVEL	Benign	0.069
Sift	Benign	0.77	T;T;T
Sift4G	Benign	1.0	T;T;T
Polyphen		0.0	B;B;B
Vest4		0.16
MVP		0.23
MPC		0.30
ClinPred		0.085	T
GERP RS		-0.42
Varity_R		0.11
gMVP		0.36

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: rs375953804; hg19: chr12-1940478;