15-55319260-C-T

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2BP4_Strong

The NM_004855.5(PIGB):​c.10C>T​(p.Pro4Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000878 in 1,606,088 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P4T) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000046 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000092 ( 0 hom. )

Consequence

PIGB
NM_004855.5 missense

Scores

2
17

Clinical Significance

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

Conservation

PhyloP100: -0.719

Publications

0 publications found
Variant links:
Genes affected
PIGB (HGNC:8959): (phosphatidylinositol glycan anchor biosynthesis class B) This gene encodes a transmembrane protein that is located in the endoplasmic reticulum and is involved in GPI-anchor biosynthesis. The glycosylphosphatidylinositol (GPI) anchor is a glycolipid found on many blood cells and serves to anchor proteins to the cell surface. This gene is thought to encode a member of a family of dolichol-phosphate-mannose (Dol-P-Man) dependent mannosyltransferases. [provided by RefSeq, Jul 2008]
PIGBOS1 (HGNC:50696): (PIGB opposite strand 1) Involved in regulation of endoplasmic reticulum unfolded protein response. Is integral component of mitochondrial outer membrane. [provided by Alliance of Genome Resources, Apr 2022]
RAB27A (HGNC:9766): (RAB27A, member RAS oncogene family) The protein encoded by this gene belongs to the small GTPase superfamily, Rab family. The protein is membrane-bound and may be involved in protein transport and small GTPase mediated signal transduction. Mutations in this gene are associated with Griscelli syndrome type 2. Alternative splicing occurs at this locus and four transcript variants encoding the same protein have been identified. [provided by RefSeq, Jul 2008]
RAB27A Gene-Disease associations (from GenCC):
  • Griscelli syndrome type 2
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, Labcorp Genetics (formerly Invitae), Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

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

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.059782237).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
PIGBNM_004855.5 linkc.10C>T p.Pro4Ser missense_variant Exon 1 of 12 ENST00000164305.10 NP_004846.4 Q92521
PIGBOS1NM_001308421.2 linkc.-472G>A upstream_gene_variant ENST00000436697.3 NP_001295350.1 A0A0B4J2F0

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
PIGBENST00000164305.10 linkc.10C>T p.Pro4Ser missense_variant Exon 1 of 12 1 NM_004855.5 ENSP00000164305.5 Q92521
PIGBENST00000566999.5 linkc.10C>T p.Pro4Ser missense_variant Exon 1 of 6 3 ENSP00000456531.1 H3BS45
PIGBOS1ENST00000436697.3 linkc.-472G>A upstream_gene_variant 2 NM_001308421.2 ENSP00000484893.1 A0A0B4J2F0

Frequencies

GnomAD3 genomes
AF:
0.0000460
AC:
7
AN:
152216
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000965
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:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000342
AC:
8
AN:
233716
AF XY:
0.0000315
show subpopulations
Gnomad AFR exome
AF:
0.0000744
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000579
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000566
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000922
AC:
134
AN:
1453872
Hom.:
0
Cov.:
31
AF XY:
0.0000955
AC XY:
69
AN XY:
722168
show subpopulations
African (AFR)
AF:
0.0000599
AC:
2
AN:
33380
American (AMR)
AF:
0.00
AC:
0
AN:
43606
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25776
East Asian (EAS)
AF:
0.0000253
AC:
1
AN:
39512
South Asian (SAS)
AF:
0.00
AC:
0
AN:
84124
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52760
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5750
European-Non Finnish (NFE)
AF:
0.000115
AC:
128
AN:
1108932
Other (OTH)
AF:
0.0000500
AC:
3
AN:
60032
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.487
Heterozygous variant carriers
0
8
16
23
31
39
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
10
20
30
40
50
<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:
0.0000460
AC:
7
AN:
152216
Hom.:
0
Cov.:
32
AF XY:
0.0000538
AC XY:
4
AN XY:
74364
show subpopulations
African (AFR)
AF:
0.0000965
AC:
4
AN:
41452
American (AMR)
AF:
0.00
AC:
0
AN:
15280
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5202
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10620
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68036
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.539
Heterozygous variant carriers
0
1
1
2
2
3
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:
0.0000680
ExAC
AF:
0.0000497
AC:
6

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
Jun 18, 2021
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.10C>T (p.P4S) alteration is located in exon 1 (coding exon 1) of the PIGB gene. This alteration results from a C to T substitution at nucleotide position 10, causing the proline (P) at amino acid position 4 to be replaced by a serine (S). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

not provided Uncertain:1
May 27, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces proline, which is neutral and non-polar, with serine, which is neutral and polar, at codon 4 of the PIGB protein (p.Pro4Ser). This variant is present in population databases (rs765931863, gnomAD 0.007%). This variant has not been reported in the literature in individuals affected with PIGB-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 C0". The serine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. 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
AlphaMissense
Benign
0.070
BayesDel_addAF
Benign
-0.22
T
BayesDel_noAF
Benign
-0.37
CADD
Benign
0.81
DANN
Benign
0.89
DEOGEN2
Benign
0.0018
T;T;T
Eigen
Benign
-1.4
Eigen_PC
Benign
-1.5
FATHMM_MKL
Benign
0.0095
N
LIST_S2
Benign
0.51
T;T;T
M_CAP
Benign
0.0057
T
MetaRNN
Benign
0.060
T;T;T
MetaSVM
Benign
-1.0
T
MutationAssessor
Benign
1.7
L;.;.
PhyloP100
-0.72
PrimateAI
Benign
0.38
T
PROVEAN
Benign
-0.47
N;N;.
REVEL
Benign
0.027
Sift
Pathogenic
0.0
D;D;.
Sift4G
Pathogenic
0.0
D;D;D
Polyphen
0.047
B;.;.
Vest4
0.090
MutPred
0.19
Gain of phosphorylation at P4 (P = 0.0101);Gain of phosphorylation at P4 (P = 0.0101);Gain of phosphorylation at P4 (P = 0.0101);
MVP
0.20
MPC
0.10
ClinPred
0.60
D
GERP RS
-4.8
PromoterAI
0.0011
Neutral
Varity_R
0.064
gMVP
0.18
Mutation Taster
=300/0
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs765931863; hg19: chr15-55611458; API