1-220213855-C-G

Variant names:

• chr1-220213855-C-G
• rs769690915
• NM_012414.4:c.304+1G>C

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PVS1 PM2

The NM_012414.4(RAB3GAP2):​c.304+1G>C variant causes a splice donor, intron change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (no stars).

• Frequency: Genomes: not found (cov: 31)
• Consequence: RAB3GAP2 NM_012414.4 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Uncertain significance no assertion criteria provided U:1
• Conservation: PhyloP100: 6.15
• Publications: 0 publications found

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 Gene-Disease associations (from GenCC):

• Martsolf syndrome 1

  Inheritance: AR Classification: DEFINITIVE Submitted by: G2P
• RAB18 deficiency

  Inheritance: AR Classification: DEFINITIVE Submitted by: Ambry Genetics
• Warburg micro syndrome

  Inheritance: AR Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
• Warburg micro syndrome 2

  Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• autosomal recessive spastic paraplegia type 69

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• cataract-intellectual disability-hypogonadism syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_012414.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	RAB3GAP2	NM_012414.4	MANE Select	c.304+1G>C		splice_donor intron	N/A	NP_036546.2

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	RAB3GAP2	ENST00000358951.7	TSL:1 MANE Select	c.304+1G>C		splice_donor intron	N/A	ENSP00000351832.2
	RAB3GAP2	ENST00000692972.1		c.304+1G>C		splice_donor intron	N/A	ENSP00000510753.1
	RAB3GAP2	ENST00000691661.1		c.316+1G>C		splice_donor intron	N/A	ENSP00000510185.1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 31

ClinVar

ClinVar submissions as Germline

Significance: Uncertain significance

Revision: no assertion criteria provided

Pathogenic	VUS	Benign	Condition
-	1	-	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.42
CADD	Pathogenic	32
DANN	Uncertain	1.0
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.95
FATHMM_MKL	Pathogenic	0.98	D
PhyloP100		6.2
GERP RS		5.7
Mutation Taster		=4/96	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
SpliceAI score (max)		0.95		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.95		Position offset: 1

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

Other links and lift over

dbSNP: rs769690915; hg19: chr1-220387197;