rs199476183

Variant names:

• chr4-186208863-A-G
• rs199476183
• NM_207352.4:c.1091-2A>G

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PVS1_Moderate PP5_Very_Strong

The NM_207352.4(CYP4V2):​c.1091-2A>G variant causes a splice acceptor, intron change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000116 in 1,461,888 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.000012 (0 hom.)
• Consequence: CYP4V2 NM_207352.4 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:8
• Conservation: PhyloP100: 9.15
• Publications: 29 publications found

Genes affected

CYP4V2 (HGNC:23198): (cytochrome P450 family 4 subfamily V member 2) This gene encodes a member of the cytochrome P450 hemethiolate protein superfamily which are involved in oxidizing various substrates in the metabolic pathway. It is implicated in the metabolism of fatty acid precursors into n-3 polyunsaturated fatty acids. Mutations in this gene result in Bietti crystalline corneoretinal dystrophy. [provided by RefSeq, Jul 2008]

CYP4V2 Gene-Disease associations (from GenCC):

• Bietti crystalline corneoretinal dystrophy

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Illumina, G2P, ClinGen, Laboratory for Molecular Medicine, Labcorp Genetics (formerly Invitae), Orphanet

ENSG00000290316 (HGNC:):

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.08555133 fraction of the gene. Cryptic splice site detected, with MaxEntScore 3.9, offset of 24, new splice context is: gtctgaccgtcccgctacAGtag. Cryptic site results in inframe change. If cryptic site found is not functional and variant results in exon loss, it results in inframe change.
• PP5: Variant 4-186208863-A-G is Pathogenic according to our data. Variant chr4-186208863-A-G is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 2191.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_207352.4. 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
	CYP4V2	NM_207352.4	MANE Select	c.1091-2A>G		splice_acceptor intron	N/A	NP_997235.3	Q6ZWL3-1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CYP4V2	ENST00000378802.5	TSL:1 MANE Select	c.1091-2A>G		splice_acceptor intron	N/A	ENSP00000368079.4	Q6ZWL3-1
	CYP4V2	ENST00000502665.1	TSL:1	n.326-2A>G		splice_acceptor intron	N/A
	CYP4V2	ENST00000507209.5	TSL:1	n.5789-2A>G		splice_acceptor intron	N/A

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.0000477 AC: 12 AN: 251494 AF XY: 0.0000589

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.000544

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000176

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000116 AC: 17 AN: 1461888 Hom.: 0 Cov.: 38 AF XY: 0.00000963 AC XY: 7 AN XY: 727246

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.000302 AC: 12 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000360 AC: 4 AN: 1112006

Other (OTH) AF: 0.0000166 AC: 1 AN: 60396

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000169 Hom.: 0

Bravo AF: 0.0000416

ExAC AF: 0.0000330 AC: 4

ClinVar

ClinVar submissions

Significance: Pathogenic/Likely pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
6	-	-	Bietti crystalline corneoretinal dystrophy (6)
1	-	-	not provided (1)
1	-	-	Retinal dystrophy (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.38	D
BayesDel_noAF	Uncertain	0.090
CADD	Pathogenic	30
DANN	Uncertain	0.99
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.86
FATHMM_MKL	Pathogenic	0.99	D
PhyloP100		9.2
GERP RS		5.5
PromoterAI		0.0028	Neutral
Mutation Taster		=6/94	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.88
SpliceAI score (max)		0.98		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.49		Position offset: -25
DS_AL_spliceai		0.98		Position offset: 2

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

Other links and lift over

dbSNP: rs199476183; hg19: chr4-187130017;