chrX-85965588-T-C

Position:

• chrX-85965588-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM2 PP3_Moderate PP5

The NM_000390.4(CHM):​c.315-1536A>G variant causes a 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. Variant has been reported in ClinVar as Likely pathogenic (no stars).

• Frequency: Genomes: not found (cov: 23)
• Consequence: CHM NM_000390.4 intron
• Clinical Significance: Likely pathogenic no assertion criteria provided P:3
• Conservation: PhyloP100: -0.184

Genes affected

CHM (HGNC:1940): (CHM Rab escort protein) This gene encodes component A of the RAB geranylgeranyl transferase holoenzyme. In the dimeric holoenzyme, this subunit binds unprenylated Rab GTPases and then presents them to the catalytic Rab GGTase subunit for the geranylgeranyl transfer reaction. Rab GTPases need to be geranylgeranyled on either one or two cysteine residues in their C-terminus to localize to the correct intracellular membrane. Mutations in this gene are a cause of choroideremia; also known as tapetochoroidal dystrophy (TCD). This X-linked disease is characterized by progressive dystrophy of the choroid, retinal pigment epithelium and retina. Alternatively spliced transcript variants have been found for this gene. [provided by RefSeq, Mar 2016]

ACMG classification

Verdict is Uncertain_significance. Variant got 5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant X-85965588-T-C is Pathogenic according to our data. Variant chrX-85965588-T-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 438064.Status of the report is no_assertion_criteria_provided, 0 stars. Variant chrX-85965588-T-C is described in Lovd as [Pathogenic]. Variant chrX-85965588-T-C is described in Lovd as [Likely_pathogenic]. Variant chrX-85965588-T-C is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CHM	NM_000390.4	c.315-1536A>G		intron_variant		ENST00000357749.7	NP_000381.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CHM	ENST00000357749.7	c.315-1536A>G		intron_variant		1	NM_000390.4	ENSP00000350386	P1
CHM	ENST00000467744.2	n.126+61903A>G		intron_variant, non_coding_transcript_variant		5

Frequencies

GnomAD3 genomes Cov.: 23

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 23

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:3

Revision: no assertion criteria provided

Submissions by phenotype

Choroideremia Pathogenic:1

Likely pathogenic, no assertion criteria provided

clinical testing

Genomics England Pilot Project, Genomics England

-

- -

Abnormality of the eye Pathogenic:1

Likely pathogenic, no assertion criteria provided

research

NIHR Bioresource Rare Diseases, University of Cambridge

Jan 01, 2015

Undetermined rare ocular disorder with frequency of less than eight patients -

Retinal dystrophy Pathogenic:1

Likely pathogenic, no assertion criteria provided

research

NIHR Bioresource Rare Diseases, University of Cambridge

Jan 01, 2015

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.93
CADD	Pathogenic	26
DANN	Benign	0.40

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.95		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.95		Position offset: -1

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

Publications

LitVar

Other links and lift over

dbSNP: rs1555955061; hg19: chrX-85220593;