NM_000390.4:c.1854A>G

Variant names:

• chrX-85864738-T-C
• rs767142766
• NM_000390.4:c.1854A>G

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 2P and 7B. PM2 BP4_Strong BP6_Moderate BP7

The NM_000390.4(CHM):​c.1854A>G​(p.Gly618Gly) variant causes a synonymous 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 benign (★).

• Frequency:
  • Genomes: not found (cov: 23)
  • Exomes 𝑓: 9.1e-7 (0 hom. 1 hem.)
  • Failed GnomAD Quality Control
• Consequence: CHM NM_000390.4 synonymous
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: 1.24
• Publications: 0 publications found

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]

CHM Gene-Disease associations (from GenCC):

• choroideremia

  Inheritance: XL Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Orphanet, Illumina, Labcorp Genetics (formerly Invitae), ClinGen

ACMG classification

Our verdict: Likely_benign. The variant received -5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.56).
• BP6: Variant X-85864738-T-C is Benign according to our data. Variant chrX-85864738-T-C is described in ClinVar as Likely_benign. ClinVar VariationId is 1613172.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP7: Synonymous conserved (PhyloP=1.24 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000390.4. 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
	CHM	NM_000390.4	MANE Select	c.1854A>G	p.Gly618Gly	synonymous	Exon 15 of 15	NP_000381.1	P24386-1
	CHM	NM_001320959.1		c.1410A>G	p.Gly470Gly	synonymous	Exon 15 of 15	NP_001307888.1	B4DRL9
	CHM	NM_001362517.1		c.1410A>G	p.Gly470Gly	synonymous	Exon 15 of 15	NP_001349446.1	B4DRL9

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CHM	ENST00000357749.7	TSL:1 MANE Select	c.1854A>G	p.Gly618Gly	synonymous	Exon 15 of 15	ENSP00000350386.2	P24386-1
	CHM	ENST00000891168.1		c.1851A>G	p.Gly617Gly	synonymous	Exon 15 of 15	ENSP00000561227.1
	CHM	ENST00000891170.1		c.1839A>G	p.Gly613Gly	synonymous	Exon 15 of 15	ENSP00000561229.1

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD2 exomes AF: 0.00000566 AC: 1 AN: 176780 AF XY: 0.00

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000128

Gnomad OTH exome AF: 0.00

GnomAD4 exome Data not reliable, filtered out with message: AS_VQSR AF: 9.14e-7 AC: 1 AN: 1094249 Hom.: 0 Cov.: 29 AF XY: 0.00000278 AC XY: 1 AN XY: 359843

African (AFR) AF: 0.00 AC: 0 AN: 26349

American (AMR) AF: 0.00 AC: 0 AN: 35080

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 19337

East Asian (EAS) AF: 0.00 AC: 0 AN: 30085

South Asian (SAS) AF: 0.00 AC: 0 AN: 53555

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 40404

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 4124

European-Non Finnish (NFE) AF: 0.00000119 AC: 1 AN: 839368

Other (OTH) AF: 0.00 AC: 0 AN: 45947

GnomAD4 genome Cov.: 23

ClinVar

ClinVar submissions

Significance: Likely benign

Revision: criteria provided, single submitter

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

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.56
CADD	Benign	2.4
DANN	Benign	0.68
PhyloP100		1.2

Splicing

Name	Calibrated prediction	Score	Prediction
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: rs767142766; hg19: chrX-85119743;