Genetic Variant NM_145239.3:c.-66+1G>A (chr16-29812324-G-A) – ACMG Classification: Pathogenic (10 pts)

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PVS1PM2

The NM_145239.3(PRRT2):c.-66+1G>A variant causes a splice donor, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000197 in 152,220 control chromosomes in the GnomAD database, with no homozygous occurrence. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 31)

Consequence

PRRT2
NM_145239.3 splice_donor, intron

Scores

Splicing: ADA: 1.000

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.755

Variant links:

Genes affected

PRRT2 (HGNC:30500): (proline rich transmembrane protein 2) This gene encodes a transmembrane protein containing a proline-rich domain in its N-terminal half. Studies in mice suggest that it is predominantly expressed in brain and spinal cord in embryonic and postnatal stages. Mutations in this gene are associated with episodic kinesigenic dyskinesia-1. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jan 2012]

PRRT2 links:

ENSG00000280893 (HGNC:):

ENSG00000280893 links:

MVP-DT (HGNC:56029): (MVP divergent transcript)

MVP-DT links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 10 ACMG points.

PVS1

Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, Cryptic splice site detected, with MaxEntScore 7.2, offset of 28, new splice context is: cggGTagga. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in frameshift change.

PM2

Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PRRT2	NM_145239.3 link	c.-66+1G>A		splice_donor_variant, intron_variant	Intron 1 of 3	ENST00000358758.12	NP_660282.2	Q7Z6L0-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PRRT2	ENST00000358758.12 link	c.-66+1G>A		splice_donor_variant, intron_variant	Intron 1 of 3	1	NM_145239.3	ENSP00000351608.7		Q7Z6L0-1
ENSG00000280893	ENST00000609618.2 link	n.-66+1G>A		splice_donor_variant, intron_variant	Intron 1 of 5	5		ENSP00000476774.2		A0A0G2JLL6

Frequencies

GnomAD3 genomes

AF:

0.0000197

AC:

AN:

152220

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000294

Gnomad OTH

AF:

0.00

GnomAD4 exome

Cov.:

GnomAD4 genome

AF:

0.0000197

AC:

AN:

152220

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74356

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000294

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000142

Hom.:

Bravo

AF:

0.0000264

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not provided

Uncertain:1

Aug 14, 2014

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

c.-66+1 G>A: IVS1+1 G>A in intron 1 of the PRRT2 gene (NM_145239.2)A variant of unknown significance has been identified in the PRRT2 gene. The c.-66+1 G>A variant has not been published as a mutation, nor has it been reported as a benign polymorphism to our knowledge. The c.-66+1 G>A variant destroys the canonical splice donor site of non-coding exon 1, either leading to the inclusion of abnormal sequence into the 5' UTR or deletion of sequence normally included in the 5' UTR. However, to our knowledge, no regulatory mutations have been reported in the PRRT2 gene. Additionally, in the absence of RNA/functional studies, the actual effect of the c.-66+1 G>A sequence change is unknown. Therefore, based on the currently available information, it is unclear whether this variant is a pathogenic mutation or a rare benign variant. The variant is found in EPILEPSY panel(s). -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Uncertain

0.060

CADD

Pathogenic

DANN

Benign

0.97

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Pathogenic

1.0

dbscSNV1_RF

Pathogenic

0.92

SpliceAI score (max)

0.99

Details are displayed if max score is > 0.2

DS_DG_spliceai

0.63

Position offset: 27

DS_DL_spliceai

0.99

Position offset: -1

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over