rs587777156

Variant names:

• chr2-231738139-C-T
• rs587777156
• NM_002601.4:c.140-1G>A

Variant summary

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

The NM_002601.4(PDE6D):​c.140-1G>A variant causes a splice acceptor, intron change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 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 Pathogenic (no stars).

• Frequency: Genomes: not found (cov: 32)
• Consequence: PDE6D NM_002601.4 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 7.57
• Publications: 1 publications found

Genes affected

PDE6D (HGNC:8788): (phosphodiesterase 6D) This gene encodes the delta subunit of rod-specific photoreceptor phosphodiesterase (PDE), a key enzyme in the phototransduction cascade. A similar protein in cow functions in solubilizing membrane-bound PDE. In addition to its role in the PDE complex, the encoded protein is thought to bind to prenyl groups of proteins to target them to subcellular organelles called cilia. Mutations in this gene are associated with Joubert syndrome-22. Alternative splicing results in multiple splice variants. [provided by RefSeq, Mar 2014]

PDE6D Gene-Disease associations (from GenCC):

• Joubert syndrome 22

  Inheritance: AR Classification: STRONG, MODERATE, LIMITED Submitted by: G2P, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• orofaciodigital syndrome type 6

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

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

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.2781457 fraction of the gene. Cryptic splice site detected, with MaxEntScore 7.4, offset of -32, new splice context is: gtcctgtggttttcatttAGaaa. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in inframe change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 2-231738139-C-T is Pathogenic according to our data. Variant chr2-231738139-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 100773.Status of the report is no_assertion_criteria_provided, 0 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_002601.4. 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
	PDE6D	NM_002601.4	MANE Select	c.140-1G>A		splice_acceptor intron	N/A	NP_002592.1
	PDE6D	NM_001291018.2		c.140-1G>A		splice_acceptor intron	N/A	NP_001277947.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PDE6D	ENST00000287600.9	TSL:1 MANE Select	c.140-1G>A		splice_acceptor intron	N/A	ENSP00000287600.4
	PDE6D	ENST00000938376.1		c.140-847G>A		intron	N/A	ENSP00000608435.1
	PDE6D	ENST00000428104.2	TSL:3	c.83-1G>A		splice_acceptor intron	N/A	ENSP00000399098.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

ClinVar

ClinVar submissions as Germline

Significance: Pathogenic

Revision: no assertion criteria provided

Pathogenic	VUS	Benign	Condition
1	-	-	Joubert syndrome 22 (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.38
CADD	Pathogenic	32
DANN	Uncertain	1.0
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.98
FATHMM_MKL	Pathogenic	0.98	D
PhyloP100		7.6
GERP RS		5.4
Mutation Taster		=1/99	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		0.78		Details are displayed if max score is > 0.2
DS_AL_spliceai		0.78		Position offset: -1

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

Other links and lift over

dbSNP: rs587777156; hg19: chr2-232602849;