rs121917888

Variant names:

• chrX-11120974-C-T
• rs121917888
• NM_005333.5:c.589C>T

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PVS1_Strong PM2 PP5

The NM_005333.5(HCCS):​c.589C>T​(p.Arg197*) variant causes a stop gained change involving the alteration of a non-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 Pathogenic (no stars).

• Frequency: Genomes: not found (cov: 23)
• Consequence: HCCS NM_005333.5 stop_gained
• Clinical Significance: Pathogenic no assertion criteria provided P:1 O:1
• Conservation: PhyloP100: 2.27
• Publications: 7 publications found

Genes affected

HCCS (HGNC:4837): (holocytochrome c synthase) The protein encoded by this gene is an enzyme that covalently links a heme group to the apoprotein of cytochrome c. Defects in this gene are a cause of microphthalmia syndromic type 7 (MCOPS7). Three transcript variants encoding the same protein have been found for this gene. [provided by RefSeq, Jan 2010]

ARHGAP6 (HGNC:676): (Rho GTPase activating protein 6) This gene encodes a member of the rhoGAP family of proteins which play a role in the regulation of actin polymerization at the plasma membrane during several cellular processes. This protein is thought to have two independent functions, one as a GTPase-activating protein with specificity for RhoA, and another as a cytoskeletal protein that promotes actin remodeling. Multiple alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

ACMG classification

Our verdict: Likely_pathogenic. The variant received 7 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most 50 bp of the penultimate exon, not predicted to undergo nonsense mediated mRNA decay. There are 6 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant X-11120974-C-T is Pathogenic according to our data. Variant chrX-11120974-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 11670.Status of the report is no_assertion_criteria_provided, 0 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_005333.5. 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
	HCCS	NM_005333.5	MANE Select	c.589C>T	p.Arg197*	stop_gained	Exon 6 of 7	NP_005324.3	P53701
	HCCS	NM_001122608.3		c.589C>T	p.Arg197*	stop_gained	Exon 6 of 7	NP_001116080.1	P53701
	HCCS	NM_001171991.3		c.589C>T	p.Arg197*	stop_gained	Exon 6 of 7	NP_001165462.1	P53701

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	HCCS	ENST00000380762.5	TSL:1 MANE Select	c.589C>T	p.Arg197*	stop_gained	Exon 6 of 7	ENSP00000370139.4	P53701
	HCCS	ENST00000380763.7	TSL:1	c.589C>T	p.Arg197*	stop_gained	Exon 6 of 7	ENSP00000370140.3	P53701
	HCCS	ENST00000321143.8	TSL:2	c.589C>T	p.Arg197*	stop_gained	Exon 6 of 7	ENSP00000326579.4	P53701

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome Cov.: 29

GnomAD4 genome Cov.: 23

Alfa AF: 0.00 Hom.: 0

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: no assertion criteria provided

Pathogenic	VUS	Benign	Condition
1	-	-	Linear skin defects with multiple congenital anomalies 1 (2)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.71	D
BayesDel_noAF	Pathogenic	0.55
CADD	Pathogenic	34
DANN	Uncertain	0.99
FATHMM_MKL	Uncertain	0.86	D
PhyloP100		2.3
Vest4		0.86
GERP RS		3.5
Mutation Taster		=2/198	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
Splicevardb		2.0
SpliceAI score (max)		0.040		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: rs121917888; hg19: chrX-11139094;