rs1240660323

Variant names:

• chr15-55319274-C-T
• rs1240660323
• NM_004855.5:c.24C>T

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 2P and 7B. PM2 BP4_Strong BP6_Moderate BP7

The NM_004855.5(PIGB):​c.24C>T​(p.Cys8Cys) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000747 in 1,606,978 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 Likely benign (★).

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000076 (0 hom.)
• Consequence: PIGB NM_004855.5 synonymous
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: 0.394
• Publications: 0 publications found

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

ACMG classification

Our verdict: Likely_benign. The variant received -5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.63).
• BP6: Variant 15-55319274-C-T is Benign according to our data. Variant chr15-55319274-C-T is described in ClinVar as [Likely_benign]. Clinvar id is 1916968.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP7: Synonymous conserved (PhyloP=0.394 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PIGB	NM_004855.5	c.24C>T	p.Cys8Cys	synonymous_variant	Exon 1 of 12	ENST00000164305.10	NP_004846.4
PIGBOS1	NM_001308421.2	c.-486G>A		upstream_gene_variant		ENST00000436697.3	NP_001295350.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PIGB	ENST00000164305.10	c.24C>T	p.Cys8Cys	synonymous_variant	Exon 1 of 12	1	NM_004855.5	ENSP00000164305.5
PIGB	ENST00000566999.5	c.24C>T	p.Cys8Cys	synonymous_variant	Exon 1 of 6	3		ENSP00000456531.1
PIGBOS1	ENST00000436697.3	c.-486G>A		upstream_gene_variant		2	NM_001308421.2	ENSP00000484893.1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152186 Hom.: 0 Cov.: 32

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: 0.0000128 AC: 3 AN: 235162 AF XY: 0.0000157

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: 0.0000188

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000756 AC: 11 AN: 1454792 Hom.: 0 Cov.: 31 AF XY: 0.00000969 AC XY: 7 AN XY: 722732

African (AFR) AF: 0.00 AC: 0 AN: 33396

American (AMR) AF: 0.00 AC: 0 AN: 43766

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25810

East Asian (EAS) AF: 0.00 AC: 0 AN: 39540

South Asian (SAS) AF: 0.0000237 AC: 2 AN: 84296

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52860

Middle Eastern (MID) AF: 0.000348 AC: 2 AN: 5750

European-Non Finnish (NFE) AF: 0.00000541 AC: 6 AN: 1109278

Other (OTH) AF: 0.0000166 AC: 1 AN: 60096

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152186 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74340

African (AFR) AF: 0.00 AC: 0 AN: 41434

American (AMR) AF: 0.00 AC: 0 AN: 15276

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: 4830

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10616

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68036

Other (OTH) AF: 0.00 AC: 0 AN: 2094

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000756

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Benign:1

Apr 10, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.63
CADD	Benign	9.7
DANN	Benign	0.81
PhyloP100		0.39
PromoterAI		-0.042	Neutral
Mutation Taster		=100/0	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

Other links and lift over

dbSNP: rs1240660323; hg19: chr15-55611472;