rs121434489

Variant names:

• chr17-2638310-C-T
• rs121434489
• NM_000430.4:c.22C>T

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.22C>T​(p.Arg8*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: PAFAH1B1 NM_000430.4 stop_gained
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:8
• Conservation: PhyloP100: 2.86
• Publications: 4 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: G2P, Labcorp Genetics (formerly Invitae)

ACMG classification

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

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant located near the start codon (<100nt), not predicted to undergo nonsense mediated mRNA decay. There are 149 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 17-2638310-C-T is Pathogenic according to our data. Variant chr17-2638310-C-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 8081.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000430.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PAFAH1B1	NM_000430.4	MANE Select	c.22C>T	p.Arg8*	stop_gained	Exon 2 of 11	NP_000421.1	P43034-1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	PAFAH1B1	ENST00000397195.10	TSL:1 MANE Select	c.22C>T	p.Arg8*	stop_gained	Exon 2 of 11	ENSP00000380378.4	P43034-1
	PAFAH1B1	ENST00000572915.6	TSL:1	n.262C>T		non_coding_transcript_exon	Exon 2 of 8
	PAFAH1B1	ENST00000570400.2	TSL:3	c.-89C>T		5_prime_UTR_premature_start_codon_gain	Exon 3 of 11	ENSP00000460258.2	A0A6Q8PFT2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Data not reliable, filtered out with message: AC0;AS_VQSR AF: 0.00 AC: 0 AN: 1460466 Hom.: 0 Cov.: 29 AF XY: 0.00 AC XY: 0 AN XY: 726578

African (AFR) AF: 0.00 AC: 0 AN: 33444

American (AMR) AF: 0.00 AC: 0 AN: 44716

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26118

East Asian (EAS) AF: 0.00 AC: 0 AN: 39660

South Asian (SAS) AF: 0.00 AC: 0 AN: 86198

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53414

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5296

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111322

Other (OTH) AF: 0.00 AC: 0 AN: 60298

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions

Significance: Pathogenic/Likely pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
3	-	-	Lissencephaly due to LIS1 mutation (3)
2	-	-	not provided (2)
1	-	-	Intellectual disability (1)
1	-	-	Lissencephaly (1)
1	-	-	Subcortical band heterotopia (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.58
CADD	Pathogenic	42
DANN	Uncertain	1.0
Eigen	Pathogenic	0.81
Eigen_PC	Pathogenic	0.69
FATHMM_MKL	Uncertain	0.82	D
PhyloP100		2.9
Vest4		0.94
GERP RS		5.3
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Mutation Taster		=2/198	disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs121434489; hg19: chr17-2541604;