chr1-220193252-G-T

Variant names:

• chr1-220193252-G-T
• rs188522997
• NM_012414.4:c.1258C>A

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM1 PM2 PP3_Moderate

The NM_012414.4(RAB3GAP2):​c.1258C>A​(p.Arg420Ser) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,630 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R420C) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: RAB3GAP2 NM_012414.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 6.15
• Publications: 7 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: Orphanet, ClinGen
• 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: Likely_pathogenic. The variant received 6 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 3 uncertain in NM_012414.4
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.875

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

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	RAB3GAP2	NM_012414.4	MANE Select	c.1258C>A	p.Arg420Ser	missense	Exon 13 of 35	NP_036546.2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	RAB3GAP2	ENST00000358951.7	TSL:1 MANE Select	c.1258C>A	p.Arg420Ser	missense	Exon 13 of 35	ENSP00000351832.2	Q9H2M9-1
	RAB3GAP2	ENST00000692972.1		c.1333C>A	p.Arg445Ser	missense	Exon 14 of 36	ENSP00000510753.1	A0A8I5KZB3
	RAB3GAP2	ENST00000691661.1		c.1270C>A	p.Arg424Ser	missense	Exon 13 of 35	ENSP00000510185.1	A0A8I5KYQ0

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251122 AF XY: 0.00

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000289

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461630 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727094

African (AFR) AF: 0.00 AC: 0 AN: 33478

American (AMR) AF: 0.0000224 AC: 1 AN: 44710

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26130

East Asian (EAS) AF: 0.00 AC: 0 AN: 39674

South Asian (SAS) AF: 0.00 AC: 0 AN: 86248

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53374

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5756

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111876

Other (OTH) AF: 0.00 AC: 0 AN: 60384

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.41	D
BayesDel_noAF	Pathogenic	0.44
CADD	Pathogenic	29
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.57	D
Eigen	Pathogenic	0.86
Eigen_PC	Pathogenic	0.86
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.97	D
M_CAP	Pathogenic	0.38	D
MetaRNN	Pathogenic	0.87	D
MetaSVM	Uncertain	0.79	D
MutationAssessor	Pathogenic	3.2	M
PhyloP100		6.2
PrimateAI	Uncertain	0.72	T
PROVEAN	Pathogenic	-5.4	D
REVEL	Pathogenic	0.67
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.97
MutPred		0.49		Loss of MoRF binding (P = 0.0186)
MVP		0.97
MPC		0.66
ClinPred		0.99	D
GERP RS		6.1
Varity_R		0.93
gMVP		0.89
Mutation Taster		=20/80	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs188522997; hg19: chr1-220366594;