rs1057520515

Variant names:

• chr17-2680321-G-A
• rs1057520515
• NM_000430.4:c.1159+1G>A

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000430.4(PAFAH1B1):​c.1159+1G>A variant causes a splice donor, intron change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: PAFAH1B1 NM_000430.4 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 10.0
• Publications: 1 publications found

Genes affected

PAFAH1B1 (HGNC:8574): (platelet activating factor acetylhydrolase 1b regulatory subunit 1) This locus was identified as encoding a gene that when mutated or lost caused the lissencephaly associated with Miller-Dieker lissencephaly syndrome. This gene encodes the non-catalytic alpha subunit of the intracellular Ib isoform of platelet-activating factor acteylhydrolase, a heterotrimeric enzyme that specifically catalyzes the removal of the acetyl group at the SN-2 position of platelet-activating factor (identified as 1-O-alkyl-2-acetyl-sn-glyceryl-3-phosphorylcholine). Two other isoforms of intracellular platelet-activating factor acetylhydrolase exist: one composed of multiple subunits, the other, a single subunit. In addition, a single-subunit isoform of this enzyme is found in serum. [provided by RefSeq, Apr 2009]

PAFAH1B1 Gene-Disease associations (from GenCC):

• lissencephaly due to LIS1 mutation

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: PanelApp Australia, Labcorp Genetics (formerly Invitae), G2P

ACMG classification

Our verdict: Pathogenic. The variant received 18 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 17-2680321-G-A is Pathogenic according to our data. Variant chr17-2680321-G-A is described in ClinVar as Pathogenic. ClinVar VariationId is 379162.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PAFAH1B1	NM_000430.4	c.1159+1G>A		splice_donor_variant, intron_variant	Intron 10 of 10	ENST00000397195.10	NP_000421.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PAFAH1B1	ENST00000397195.10	c.1159+1G>A		splice_donor_variant, intron_variant	Intron 10 of 10	1	NM_000430.4	ENSP00000380378.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Lissencephaly due to LIS1 mutation Pathogenic:2

-

Medical Genetics Laboratory, Niloo Shiraz Laboratory

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The identified variant, NM_000430.4:c.1159+1G>A, is located at a canonical splice donor site in intron 10 of the PAFAH1B1 gene. This variant is predicted to disrupt normal RNA splicing, potentially leading to exon skipping or activation of a cryptic splice site. Notably, this variant is absent from major population databases such as gnomAD, and is also not found in our internal dataset (Niloo Genome). The variant was detected in a patient from a non-consanguineous family, presenting with clinical features consistent with PAFAH1B1-related disorders, supporting the likely pathogenic role of this splice-site alteration. -

Sep 21, 2016

Genetic Services Laboratory, University of Chicago

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided Pathogenic:1

Mar 05, 2015

GeneDx

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.1159+1 G>A splice site variant in the PAFAH1B1 gene destroys the canonical splice donor site inintron 10. It is predicted to cause abnormal gene splicing, either leading to an abnormal message that is subjectto nonsense-mediated mRNA decay, or to an abnormal protein product if the message is used for proteintranslation. Although this variant has not been previously reported to our knowledge, however we consider it to be a pathogenic variant. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.41
CADD	Pathogenic	34
DANN	Uncertain	1.0
Eigen	Pathogenic	1.2
Eigen_PC	Pathogenic	1.1
FATHMM_MKL	Pathogenic	1.0	D
PhyloP100		10
GERP RS		5.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.8
Mutation Taster		=0/100	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		0.96		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.96		Position offset: -1

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

Other links and lift over

dbSNP: rs1057520515; hg19: chr17-2583615;