X-63678332-T-C

Variant names:

• chrX-63678332-T-C
• rs1464003224
• NM_001353921.2:c.815+8A>G

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 2P and 6B. PM2 BP4_Strong BP6_Moderate

The NM_001353921.2(ARHGEF9):​c.815+8A>G variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Likely benign (★).

• Frequency: Genomes: not found (cov: 23)
• Consequence: ARHGEF9 NM_001353921.2 splice_region, intron
• Scores: Splicing: ADA: 0.00007483
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: 0.663
• Publications: 0 publications found

Genes affected

ARHGEF9 (HGNC:14561): (Cdc42 guanine nucleotide exchange factor 9) The protein encoded by this gene is a Rho-like GTPase that switches between the active (GTP-bound) state and inactive (GDP-bound) state to regulate CDC42 and other genes. This brain-specific protein also acts as an adaptor protein for the recruitment of gephyrin and together these proteins facilitate receceptor recruitement in GABAnergic and glycinergic synapses. Defects in this gene are the cause of startle disease with epilepsy (STHEE), also known as hyperekplexia with epilepsy, as well as several other types of cognitive disability. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2017]

ARHGEF9 Gene-Disease associations (from GenCC):

• developmental and epileptic encephalopathy, 8

  Inheritance: XL Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, G2P, Labcorp Genetics (formerly Invitae), Orphanet
• X-linked complex neurodevelopmental disorder

  Inheritance: XL Classification: MODERATE Submitted by: ClinGen

ACMG classification

Our verdict: Likely_benign. The variant received -4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.84).
• BP6: Variant X-63678332-T-C is Benign according to our data. Variant chrX-63678332-T-C is described in ClinVar as Likely_benign. ClinVar VariationId is 465082.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
ARHGEF9	NM_001353921.2	c.815+8A>G		splice_region_variant, intron_variant	Intron 5 of 9	ENST00000671741.2	NP_001340850.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ARHGEF9	ENST00000671741.2	c.815+8A>G		splice_region_variant, intron_variant	Intron 5 of 9		NM_001353921.2	ENSP00000500715.1

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome Cov.: 29

GnomAD4 genome Cov.: 23

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

Developmental and epileptic encephalopathy, 8 Benign:1

Sep 25, 2017

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.84
CADD	Benign	5.1
DANN	Benign	0.51
PhyloP100		0.66

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.000075
dbscSNV1_RF	Benign	0.0
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

Other links and lift over

dbSNP: rs1464003224; hg19: chrX-62898212;