2-196847946-C-G

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1PM2PP5_Moderate

The NM_024989.4(PGAP1):​c.1952+1G>C variant causes a splice donor, intron change. The variant allele was found at a frequency of 0.00000193 in 1,557,508 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 Pathogenic (★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

PGAP1
NM_024989.4 splice_donor, intron

Scores

4
2
1
Splicing: ADA: 1.000
2

Clinical Significance

Pathogenic criteria provided, single submitter P:1

Conservation

PhyloP100: 3.63

Publications

1 publications found
Variant links:
Genes affected
PGAP1 (HGNC:25712): (post-GPI attachment to proteins inositol deacylase 1) The protein encoded by this gene functions early in the glycosylphosphatidylinositol (GPI) biosynthetic pathway, catalyzing the inositol deacylation of GPI. The encoded protein is required for the production of GPI that can attach to proteins, and this may be an important factor in the transport of GPI-anchored proteins from the endoplasmic reticulum to the Golgi. Defects in this gene are a cause an autosomal recessive form of cognitive impairment. [provided by RefSeq, Jul 2017]
PGAP1 Gene-Disease associations (from GenCC):
  • intellectual disability, autosomal recessive 42
    Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
  • autosomal recessive non-syndromic intellectual disability
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • autosomal recessive spastic paraplegia type 67
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 12 ACMG points.

PVS1
Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 2-196847946-C-G is Pathogenic according to our data. Variant chr2-196847946-C-G is described in ClinVar as Pathogenic. ClinVar VariationId is 1072363.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
PGAP1NM_024989.4 linkc.1952+1G>C splice_donor_variant, intron_variant Intron 21 of 26 ENST00000354764.9 NP_079265.2 Q75T13-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
PGAP1ENST00000354764.9 linkc.1952+1G>C splice_donor_variant, intron_variant Intron 21 of 26 1 NM_024989.4 ENSP00000346809.3 Q75T13-1
PGAP1ENST00000423035.5 linkn.*1883+1G>C splice_donor_variant, intron_variant Intron 22 of 27 1 ENSP00000415405.1 F8WD75
PGAP1ENST00000470179.5 linkn.1417G>C non_coding_transcript_exon_variant Exon 17 of 22 2
PGAP1ENST00000409475.5 linkc.*80G>C 3_prime_UTR_variant Exon 20 of 20 2 ENSP00000387028.1 Q75T13-3

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
151918
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000918
AC:
2
AN:
217908
AF XY:
0.00000844
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000779
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000142
AC:
2
AN:
1405590
Hom.:
0
Cov.:
27
AF XY:
0.00000286
AC XY:
2
AN XY:
699230
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
30882
American (AMR)
AF:
0.0000554
AC:
2
AN:
36100
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
24676
East Asian (EAS)
AF:
0.00
AC:
0
AN:
37492
South Asian (SAS)
AF:
0.00
AC:
0
AN:
76802
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
51962
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5598
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1084042
Other (OTH)
AF:
0.00
AC:
0
AN:
58036
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.625
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
AF:
0.00000658
AC:
1
AN:
151918
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74190
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41374
American (AMR)
AF:
0.00
AC:
0
AN:
15254
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10584
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
67894
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Intellectual disability, autosomal recessive 42 Pathogenic:1
Jun 27, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

For these reasons, this variant has been classified as Pathogenic. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. ClinVar contains an entry for this variant (Variation ID: 1072363). Disruption of this splice site has been observed in individual(s) with hereditary spastic paraplegia (PMID: 24482476). It has also been observed to segregate with disease in related individuals. This variant is not present in population databases (gnomAD no frequency). This sequence change affects a donor splice site in intron 21 of the PGAP1 gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in PGAP1 are known to be pathogenic (PMID: 17711852, 26050939, 27848944). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.63
D
BayesDel_noAF
Pathogenic
0.32
CADD
Pathogenic
30
DANN
Uncertain
0.99
Eigen
Pathogenic
0.98
Eigen_PC
Pathogenic
0.79
FATHMM_MKL
Uncertain
0.95
D
PhyloP100
3.6
GERP RS
4.2
Mutation Taster
=2/98
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
1.0
dbscSNV1_RF
Pathogenic
0.94
SpliceAI score (max)
0.99
Details are displayed if max score is > 0.2
DS_DL_spliceai
0.99
Position offset: 1

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

Publications

Other links and lift over

dbSNP: rs587777202; hg19: chr2-197712670; API