rs1553278790

Positions:

• chr1-220212963-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_012414.4(RAB3GAP2):​c.310T>C​(p.Trp104Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 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)
• Consequence: RAB3GAP2 NM_012414.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 8.12

Genes affected

RAB3GAP2 (HGNC:17168): (RAB3 GTPase activating non-catalytic protein subunit 2) The protein encoded by this gene belongs to the RAB3 protein family, members of which are involved in regulated exocytosis of neurotransmitters and hormones. This protein forms the Rab3 GTPase-activating complex with RAB3GAP1, where it constitutes the regulatory subunit, whereas the latter functions as the catalytic subunit. This gene has the highest level of expression in the brain, consistent with it having a key role in neurodevelopment. Mutations in this gene are associated with Martsolf syndrome.[provided by RefSeq, Oct 2009]

RAB3GAP2 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.888

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
RAB3GAP2	NM_012414.4	c.310T>C	p.Trp104Arg	missense_variant	4/35	ENST00000358951.7	NP_036546.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
RAB3GAP2	ENST00000358951.7	c.310T>C	p.Trp104Arg	missense_variant	4/35	1	NM_012414.4	ENSP00000351832.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 29

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Martsolf syndrome;C3280214:Warburg micro syndrome 2 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jul 12, 2017

This sequence change replaces tryptophan with arginine at codon 104 of the RAB3GAP2 protein (p.Trp104Arg). The tryptophan residue is moderately conserved and there is a moderate physicochemical difference between tryptophan and arginine. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals with RAB3GAP2-related disease. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). 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	0.98
BayesDel_addAF	Pathogenic	0.29	D
BayesDel_noAF	Pathogenic	0.17
CADD	Uncertain	25
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.45	T
Eigen	Uncertain	0.57
Eigen_PC	Uncertain	0.54
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Benign	0.81	T
M_CAP	Benign	0.049	D
MetaRNN	Pathogenic	0.89	D
MetaSVM	Benign	-0.76	T
MutationAssessor	Uncertain	2.8	M
PrimateAI	Uncertain	0.78	T
PROVEAN	Pathogenic	-10	D
REVEL	Uncertain	0.56
Sift	Uncertain	0.0050	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.94
MutPred		0.63		Gain of disorder (P = 0.0113);
MVP		0.46
MPC		0.56
ClinPred		1.0	D
GERP RS		4.3
Varity_R		0.84
gMVP		0.73

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: rs1553278790; hg19: chr1-220386305;