17-2676606-C-G

Variant names:

• chr17-2676606-C-G
• NM_000430.4:c.1002C>G
• PAFAH1B1 p.Leu334Leu

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 2P and 3B. PM2 BP4_Moderate BP7

The NM_000430.4(PAFAH1B1):​c.1002C>G​(p.Leu334Leu) variant causes a splice region, synonymous change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. L334L) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 33)
• Consequence: PAFAH1B1 NM_000430.4 splice_region, synonymous
• Scores: Splicing: ADA: 0.00006146
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.0520
• Publications: 0 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: Likely_benign. The variant received -1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.41).
• BP7: Synonymous conserved (PhyloP=0.052 with no splicing effect.

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.1002C>G	p.Leu334Leu	splice_region synonymous	Exon 9 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.1002C>G	p.Leu334Leu	splice_region synonymous	Exon 9 of 11	ENSP00000380378.4	P43034-1
	PAFAH1B1	ENST00000572915.6	TSL:1	n.676+2510C>G		intron	N/A
	PAFAH1B1	ENST00000674608.1		c.1056C>G	p.Leu352Leu	splice_region synonymous	Exon 10 of 12	ENSP00000501976.1	A0A6Q8PFU3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 24

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.41
CADD	Benign	0.23
DANN	Benign	0.69
PhyloP100		0.052

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.000061
dbscSNV1_RF	Benign	0.14
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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

hg19: chr17-2579900;