16-575836-C-T

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 0P and 2B. BP4_Moderate

The NM_004204.5(PIGQ):​c.690-3C>T variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000493 in 1,561,148 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000072 ( 0 hom., cov: 34)
Exomes 𝑓: 0.000047 ( 0 hom. )

Consequence

PIGQ
NM_004204.5 splice_region, intron

Scores

2
Splicing: ADA: 0.001683
2

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 1.29

Publications

0 publications found
Variant links:
Genes affected
PIGQ (HGNC:14135): (phosphatidylinositol glycan anchor biosynthesis class Q) This gene is involved in the first step in glycosylphosphatidylinositol (GPI)-anchor biosynthesis. The GPI-anchor is a glycolipid found on many blood cells and serves to anchor proteins to the cell surface. This gene encodes a N-acetylglucosaminyl transferase component that is part of the complex that catalyzes transfer of N-acetylglucosamine (GlcNAc) from UDP-GlcNAc to phosphatidylinositol (PI). Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jun 2012]
PIGQ Gene-Disease associations (from GenCC):
  • developmental and epileptic encephalopathy, 77
    Inheritance: AR Classification: STRONG, MODERATE, LIMITED Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), G2P
  • genetic developmental and epileptic encephalopathy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -2 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.45).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
PIGQNM_004204.5 linkc.690-3C>T splice_region_variant, intron_variant Intron 2 of 10 ENST00000321878.10 NP_004195.2
PIGQNM_148920.4 linkc.690-3C>T splice_region_variant, intron_variant Intron 2 of 9 NP_683721.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
PIGQENST00000321878.10 linkc.690-3C>T splice_region_variant, intron_variant Intron 2 of 10 1 NM_004204.5 ENSP00000326674.6

Frequencies

GnomAD3 genomes
AF:
0.0000723
AC:
11
AN:
152174
Hom.:
0
Cov.:
34
show subpopulations
Gnomad AFR
AF:
0.000145
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:
0.0000735
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000230
AC:
4
AN:
174244
AF XY:
0.0000323
show subpopulations
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:
0.0000561
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000468
AC:
66
AN:
1408974
Hom.:
0
Cov.:
33
AF XY:
0.0000546
AC XY:
38
AN XY:
696304
show subpopulations
African (AFR)
AF:
0.0000311
AC:
1
AN:
32158
American (AMR)
AF:
0.00
AC:
0
AN:
38150
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25322
East Asian (EAS)
AF:
0.00
AC:
0
AN:
36716
South Asian (SAS)
AF:
0.00
AC:
0
AN:
80290
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
47702
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5710
European-Non Finnish (NFE)
AF:
0.0000553
AC:
60
AN:
1084568
Other (OTH)
AF:
0.0000857
AC:
5
AN:
58358
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.484
Heterozygous variant carriers
0
4
8
13
17
21
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000723
AC:
11
AN:
152174
Hom.:
0
Cov.:
34
AF XY:
0.0000538
AC XY:
4
AN XY:
74336
show subpopulations
African (AFR)
AF:
0.000145
AC:
6
AN:
41430
American (AMR)
AF:
0.00
AC:
0
AN:
15286
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5194
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10624
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000735
AC:
5
AN:
68020
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.548
Heterozygous variant carriers
0
1
2
3
4
5
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.0000393
Hom.:
0
Bravo
AF:
0.0000378

ClinVar

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

Submissions by phenotype

Epilepsy Uncertain:1
Aug 28, 2021
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change falls in intron 2 of the PIGQ gene. It does not directly change the encoded amino acid sequence of the PIGQ protein. It affects a nucleotide within the consensus splice site of the intron. This variant is present in population databases (rs370348620, ExAC 0.01%). This variant has not been reported in the literature in individuals affected with PIGQ-related conditions. ClinVar contains an entry for this variant (Variation ID: 456052). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant is not likely to affect RNA splicing. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.45
CADD
Benign
6.4
DANN
Benign
0.65
PhyloP100
1.3

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.0017
dbscSNV1_RF
Benign
0.12
SpliceAI score (max)
0.050
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs370348620; hg19: chr16-625836; API