rs769428343

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 0P and 4B. BP4_Strong

The NM_176787.5(PIGN):​c.1646T>C​(p.Leu549Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000818 in 1,589,746 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000056 ( 0 hom. )

Consequence

PIGN
NM_176787.5 missense

Scores

4
14

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 2.58

Publications

0 publications found
Variant links:
Genes affected
PIGN (HGNC:8967): (phosphatidylinositol glycan anchor biosynthesis class N) This gene encodes a protein that is involved 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 protein is expressed in the endoplasmic reticulum and transfers phosphoethanolamine (EtNP) to the first mannose of the GPI anchor. Two alternatively spliced variants, which encode an identical isoform, have been reported. [provided by RefSeq, Jul 2008]
PIGN Gene-Disease associations (from GenCC):
  • multiple congenital anomalies-hypotonia-seizures syndrome 1
    Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, G2P, Orphanet, ClinGen, PanelApp Australia
  • Fryns syndrome
    Inheritance: AR 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 -4 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.024670362).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_176787.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
PIGN
NM_176787.5
MANE Select
c.1646T>Cp.Leu549Ser
missense
Exon 18 of 31NP_789744.1
PIGN
NM_001438896.1
c.1646T>Cp.Leu549Ser
missense
Exon 18 of 32NP_001425825.1
PIGN
NM_012327.6
c.1646T>Cp.Leu549Ser
missense
Exon 17 of 30NP_036459.1

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
PIGN
ENST00000640252.2
TSL:1 MANE Select
c.1646T>Cp.Leu549Ser
missense
Exon 18 of 31ENSP00000492233.1
PIGN
ENST00000400334.7
TSL:1
c.1646T>Cp.Leu549Ser
missense
Exon 17 of 30ENSP00000383188.2
PIGN
ENST00000638424.1
TSL:5
n.1646T>C
non_coding_transcript_exon
Exon 16 of 29ENSP00000491963.1

Frequencies

GnomAD3 genomes
AF:
0.0000328
AC:
5
AN:
152230
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000771
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000652
AC:
14
AN:
214582
AF XY:
0.0000784
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000320
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000833
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000557
AC:
8
AN:
1437516
Hom.:
0
Cov.:
29
AF XY:
0.00000702
AC XY:
5
AN XY:
712540
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
32870
American (AMR)
AF:
0.0000239
AC:
1
AN:
41772
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25542
East Asian (EAS)
AF:
0.000181
AC:
7
AN:
38654
South Asian (SAS)
AF:
0.00
AC:
0
AN:
81890
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52072
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5746
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1099342
Other (OTH)
AF:
0.00
AC:
0
AN:
59628
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.469
Heterozygous variant carriers
0
1
2
2
3
4
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome 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
GnomAD4 genome
AF:
0.0000328
AC:
5
AN:
152230
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74370
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41462
American (AMR)
AF:
0.0000654
AC:
1
AN:
15286
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.000771
AC:
4
AN:
5186
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10632
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68040
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.555
Heterozygous variant carriers
0
0
1
1
2
2
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:
0.00
Hom.:
0
Bravo
AF:
0.0000302
ExAC
AF:
0.0000999
AC:
12

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Inborn genetic diseases Uncertain:1
May 18, 2023
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.1646T>C (p.L549S) alteration is located in exon 18 (coding exon 15) of the PIGN gene. This alteration results from a T to C substitution at nucleotide position 1646, causing the leucine (L) at amino acid position 549 to be replaced by a serine (S). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear.

Multiple congenital anomalies-hypotonia-seizures syndrome 1 Uncertain:1
Aug 24, 2021
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces leucine with serine at codon 549 of the PIGN protein (p.Leu549Ser). The leucine residue is moderately conserved and there is a large physicochemical difference between leucine and serine. This variant is present in population databases (rs769428343, ExAC 0.4%). This variant has not been reported in the literature in individuals affected with PIGN-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C25". The serine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. 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 v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.17
BayesDel_addAF
Benign
-0.24
T
BayesDel_noAF
Benign
-0.12
CADD
Benign
16
DANN
Uncertain
0.99
DEOGEN2
Benign
0.20
T
Eigen
Benign
-0.27
Eigen_PC
Benign
-0.23
FATHMM_MKL
Benign
0.63
D
LIST_S2
Benign
0.74
T
M_CAP
Benign
0.016
T
MetaRNN
Benign
0.025
T
MetaSVM
Benign
-0.90
T
MutationAssessor
Uncertain
2.5
M
PhyloP100
2.6
PrimateAI
Benign
0.31
T
PROVEAN
Uncertain
-3.0
D
REVEL
Benign
0.27
Sift
Benign
0.047
D
Sift4G
Uncertain
0.029
D
Polyphen
0.19
B
Vest4
0.55
MutPred
0.70
Loss of stability (P = 0.0989)
MVP
0.76
MPC
0.036
ClinPred
0.17
T
GERP RS
6.1
Varity_R
0.23
gMVP
0.51
Mutation Taster
=70/30
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.0
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: rs769428343; hg19: chr18-59774247; API