chr15-55319249-G-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.-2G>T variant causes a 5 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000935 in 1,604,196 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000090 ( 0 hom. )

Consequence

PIGB
NM_004855.5 5_prime_UTR

Scores

2

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.117

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 (BayesDel_noAF=-0.79).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
PIGBNM_004855.5 linkc.-2G>T 5_prime_UTR_variant Exon 1 of 12 ENST00000164305.10 NP_004846.4 Q92521
PIGBOS1NM_001308421.2 linkc.-461C>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.-2G>T 5_prime_UTR_variant Exon 1 of 12 1 NM_004855.5 ENSP00000164305.5 Q92521
PIGBENST00000566999.5 linkc.-2G>T 5_prime_UTR_variant Exon 1 of 6 3 ENSP00000456531.1 H3BS45
PIGBOS1ENST00000436697.3 linkc.-461C>A upstream_gene_variant 2 NM_001308421.2 ENSP00000484893.1 A0A0B4J2F0

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152224
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:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000868
AC:
2
AN:
230488
AF XY:
0.00000799
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:
0.0000192
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000895
AC:
13
AN:
1451972
Hom.:
0
Cov.:
31
AF XY:
0.00000832
AC XY:
6
AN XY:
721072
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33364
American (AMR)
AF:
0.00
AC:
0
AN:
43294
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25684
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39468
South Asian (SAS)
AF:
0.00
AC:
0
AN:
83788
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52654
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5742
European-Non Finnish (NFE)
AF:
0.0000117
AC:
13
AN:
1107996
Other (OTH)
AF:
0.00
AC:
0
AN:
59982
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.513
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

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:
0.0000131
AC:
2
AN:
152224
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74364
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41450
American (AMR)
AF:
0.00
AC:
0
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5200
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4836
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:
0.0000294
AC:
2
AN:
68044
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
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:
0.0000227

ClinVar

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

Submissions by phenotype

not specified Uncertain:1
Dec 15, 2023
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: PIGB c.-2G>T is located in the untranslated mRNA region upstream of the initiation codon. The variant allele was found at a frequency of 8.7e-06 in 230488 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.-2G>T in individuals affected with Developmental And Epileptic Encephalopathy, 80 and no experimental evidence demonstrating its impact on protein function have been reported. No submitters have cited clinical-significance assessments for this variant to ClinVar after 2014. Based on the evidence outlined above, the variant was classified as uncertain significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.79
CADD
Benign
5.0
DANN
Benign
0.71
PhyloP100
0.12
PromoterAI
0.058
Neutral

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: rs371584829; hg19: chr15-55611447; COSMIC: COSV51243688; COSMIC: COSV51243688; API