1-155900430-C-G

Position:

• chr1-155900430-C-G

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 4P and 2B. PM1 PM2 BP4_Moderate

The NM_006912.6(RIT1):​c.618G>C​(p.Arg206Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,856 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 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. R206K) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: RIT1 NM_006912.6 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: -0.0640

Genes affected

RIT1 (HGNC:10023): (Ras like without CAAX 1) This gene encodes a member of a subfamily of Ras-related GTPases. The encoded protein is involved in regulating p38 MAPK-dependent signaling cascades related to cellular stress. This protein also cooperates with nerve growth factor to promote neuronal development and regeneration. Alternate splicing results in multiple transcript variants. [provided by RefSeq, Feb 2012]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM1: In a chain GTP-binding protein Rit1 (size 218) in uniprot entity RIT1_HUMAN there are 55 pathogenic changes around while only 10 benign (85%) in NM_006912.6
• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.15580231).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
RIT1	NM_006912.6	c.618G>C	p.Arg206Ser	missense_variant	6/6	ENST00000368323.8	NP_008843.1
RIT1	NM_001256821.2	c.669G>C	p.Arg223Ser	missense_variant	6/6		NP_001243750.1
RIT1	NM_001256820.2	c.510G>C	p.Arg170Ser	missense_variant	5/5		NP_001243749.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
RIT1	ENST00000368323.8	c.618G>C	p.Arg206Ser	missense_variant	6/6	1	NM_006912.6	ENSP00000357306.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461856 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 727232

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: 0.00000270

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Noonan syndrome 8 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Mar 08, 2022

This sequence change replaces arginine, which is basic and polar, with serine, which is neutral and polar, at codon 206 of the RIT1 protein (p.Arg206Ser). 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 RIT1 protein function. This variant has not been reported in the literature in individuals affected with RIT1-related conditions. This variant is not present in population databases (gnomAD no frequency). -

Cardiovascular phenotype Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Sep 20, 2024

The p.R206S variant (also known as c.618G>C), located in coding exon 5 of the RIT1 gene, results from a G to C substitution at nucleotide position 618. The arginine at codon 206 is replaced by serine, an amino acid with dissimilar properties. This amino acid position is conserved. In addition, this alteration is predicted to be tolerated by in silico analysis. Based on the available evidence, the clinical significance of this variant remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.57
BayesDel_addAF	Benign	-0.056	T
BayesDel_noAF	Benign	-0.32
CADD	Benign	19
DANN	Benign	0.96
DEOGEN2	Benign	0.23	T;.;.
Eigen	Benign	-0.75
Eigen_PC	Benign	-0.66
FATHMM_MKL	Uncertain	0.77	D
LIST_S2	Benign	0.85	D;D;D
M_CAP	Benign	0.029	D
MetaRNN	Benign	0.16	T;T;T
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	0.34	N;.;.
PrimateAI	Uncertain	0.68	T
PROVEAN	Benign	-1.2	N;N;N
REVEL	Benign	0.23
Sift	Benign	0.076	T;T;T
Sift4G	Benign	0.15	T;T;T
Polyphen		0.34	B;.;.
Vest4		0.42
MutPred		0.29		Gain of phosphorylation at R206 (P = 0.0068);.;.;
MVP		0.62
MPC		0.90
ClinPred		0.57	D
GERP RS		-2.8
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.090
gMVP		0.75

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: rs1673288777; hg19: chr1-155870221;