5-14143784-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 3P and 2B. PM2 PP2 BP4_Moderate

The NM_007118.4(TRIO):c.59C>T(p.Ala20Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000488 in 1,025,564 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A20T) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.0000068 (0 hom., cov: 31)
  • Exomes 𝑓: 0.0000046 (0 hom.)
• Consequence: TRIO NM_007118.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -1.72

Genes affected

TRIO (HGNC:12303): (trio Rho guanine nucleotide exchange factor) This gene encodes a large protein that functions as a GDP to GTP exchange factor. This protein promotes the reorganization of the actin cytoskeleton, thereby playing a role in cell migration and growth. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Dec 2015]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant where missense usually causes diseases, TRIO
• BP4: Computational evidence support a benign effect (MetaRNN=0.12553027).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TRIO	NM_007118.4	c.59C>T	p.Ala20Val	missense_variant	1/57	ENST00000344204.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TRIO	ENST00000344204.9	c.59C>T	p.Ala20Val	missense_variant	1/57	1	NM_007118.4	P1
TRIO	ENST00000698541.1	c.59C>T	p.Ala20Val	missense_variant	1/37
TRIO	ENST00000502816.1	n.83C>T		non_coding_transcript_exon_variant	1/5	2
TRIO	ENST00000505971.5	n.83C>T		non_coding_transcript_exon_variant	1/4	3

Frequencies

GnomAD3 genomes AF: 0.00000682 AC: 1 AN: 146724 Hom.: 0 Cov.: 31

Gnomad AFR AF: 0.0000245

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000455 AC: 4 AN: 878840 Hom.: 0 Cov.: 29 AF XY: 0.00000244 AC XY: 1 AN XY: 409656

Gnomad4 AFR exome AF: 0.000179

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: 0.00

Gnomad4 OTH exome AF: 0.0000332

GnomAD4 genome AF: 0.00000682 AC: 1 AN: 146724 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 71408

Gnomad4 AFR AF: 0.0000245

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Feb 11, 2022

The frequency data for this variant in the population databases is considered unreliable, as metrics indicate insufficient coverage at this position in the gnomAD database. This sequence change replaces alanine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 20 of the TRIO protein (p.Ala20Val). This variant has not been reported in the literature in individuals affected with TRIO-related conditions. 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. 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 not expected to disrupt TRIO protein function. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.12
BayesDel_addAF	Benign	-0.16	T
BayesDel_noAF	Benign	-0.46
Cadd	Benign	19
Dann	Uncertain	0.99
DEOGEN2	Benign	0.048	T
Eigen	Benign	-1.0
Eigen_PC	Benign	-1.1
FATHMM_MKL	Benign	0.024	N
LIST_S2	Benign	0.39	T
M_CAP	Pathogenic	0.66	D
MetaRNN	Benign	0.13	T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.0	N
MutationTaster	Benign	1.0	N;N
PrimateAI	Pathogenic	0.82	D
PROVEAN	Benign	0.040	N
REVEL	Benign	0.081
Sift	Benign	0.52	T
Sift4G	Benign	1.0	T
Polyphen		0.46	P
Vest4		0.13
MutPred		0.28		Gain of catalytic residue at A20 (P = 0.0676);
MVP		0.56
MPC		0.83
ClinPred		0.092	T
GERP RS		-0.29
Varity_R		0.046
gMVP		0.20

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: rs1581221675; hg19: chr5-14143893;