1-109573775-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM1 PP3_Moderate

The NM_006496.4(GNAI3):c.157A>G(p.Met53Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000548 in 1,459,412 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000055 (0 hom.)
• Consequence: GNAI3 NM_006496.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.32

Genes affected

GNAI3 (HGNC:4387): (G protein subunit alpha i3) Guanine nucleotide-binding proteins (G proteins) are involved as modulators or transducers in various transmembrane signaling pathways. G proteins are composed of 3 units: alpha, beta and gamma. This gene encodes an alpha subunit and belongs to the G-alpha family. Mutation in this gene, resulting in a gly40-to-arg substitution, is associated with auriculocondylar syndrome, and shown to affect downstream targets in the G protein-coupled endothelin receptor pathway. [provided by RefSeq, Jun 2012]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 2 uncertain in NM_006496.4
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.938

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GNAI3	NM_006496.4	c.157A>G	p.Met53Val	missense_variant	2/9	ENST00000369851.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GNAI3	ENST00000369851.7	c.157A>G	p.Met53Val	missense_variant	2/9	1	NM_006496.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000796 AC: 2 AN: 251262 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135796

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000176

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000548 AC: 8 AN: 1459412 Hom.: 0 Cov.: 28 AF XY: 0.00000551 AC XY: 4 AN XY: 726174

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: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000631

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000282 Hom.: 0

Bravo AF: 0.00000378

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

Jan 02, 2024

This sequence change replaces methionine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 53 of the GNAI3 protein (p.Met53Val). This variant is present in population databases (no rsID available, gnomAD 0.002%). This variant has not been reported in the literature in individuals affected with GNAI3-related conditions. ClinVar contains an entry for this variant (Variation ID: 1973080). 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 GNAI3 protein function with a negative predictive value of 80%. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.94
BayesDel_addAF	Pathogenic	0.46	D
BayesDel_noAF	Pathogenic	0.43
Cadd	Pathogenic	35
Dann	Uncertain	0.99
DEOGEN2	Pathogenic	0.91	D
Eigen	Pathogenic	0.78
Eigen_PC	Pathogenic	0.73
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.97	D
M_CAP	Pathogenic	0.34	D
MetaRNN	Pathogenic	0.94	D
MetaSVM	Uncertain	0.79	D
MutationAssessor	Pathogenic	3.3	M
MutationTaster	Benign	1.0	D
PrimateAI	Pathogenic	0.90	D
PROVEAN	Uncertain	-3.1	D
REVEL	Pathogenic	0.95
Sift	Uncertain	0.0010	D
Sift4G	Uncertain	0.034	D
Polyphen		0.86	P
Vest4		0.76
MutPred		0.81		Gain of methylation at K54 (P = 0.0346);
MVP		0.96
MPC		1.3
ClinPred		0.95	D
GERP RS		5.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.91
gMVP		0.88

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.90		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.90		Position offset: -1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs981945258; hg19: chr1-110116397;