rs1057518936

Positions:

• chr19-7541025-C-A
• chr19-7541025-C-G

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM2 PP2 PP3_Strong PP5_Moderate

The NM_001166114.2(PNPLA6):​c.898C>A​(p.Pro300Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000343 in 1,458,496 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: PNPLA6 NM_001166114.2 missense
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 7.83

Genes affected

PNPLA6 (HGNC:16268): (patatin like phospholipase domain containing 6) This gene encodes a phospholipase that deacetylates intracellular phosphatidylcholine to produce glycerophosphocholine. It is thought to function in neurite outgrowth and process elongation during neuronal differentiation. The protein is anchored to the cytoplasmic face of the endoplasmic reticulum in both neurons and non-neuronal cells. Mutations in this gene result in autosomal recessive spastic paraplegia, and the protein is the target for neurodegeneration induced by organophosphorus compounds and chemical warfare agents. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Oct 2009]

ACMG classification

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), PNPLA6. . Gene score misZ 4.3547 (greater than the threshold 3.09). Trascript score misZ 3.5139 (greater than threshold 3.09). GenCC has associacion of gene with trichomegaly-retina pigmentary degeneration-dwarfism syndrome, ataxia-hypogonadism-choroidal dystrophy syndrome, Laurence-Moon syndrome, cerebellar ataxia-hypogonadism syndrome, retinal dystrophy-ataxia-pituitary hormone abnormality-hypogonadism syndrome, PNPLA6-related spastic paraplegia with or without ataxia, hereditary spastic paraplegia 39.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.967
• PP5: Variant 19-7541025-C-A is Pathogenic according to our data. Variant chr19-7541025-C-A is described in ClinVar as [Pathogenic]. Clinvar id is 854646.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PNPLA6	NM_001166114.2	c.898C>A	p.Pro300Thr	missense_variant	7/32	ENST00000600737.6	NP_001159586.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PNPLA6	ENST00000600737.6	c.898C>A	p.Pro300Thr	missense_variant	7/32	1	NM_001166114.2	ENSP00000473211.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000343 AC: 5 AN: 1458496 Hom.: 0 Cov.: 34 AF XY: 0.00000689 AC XY: 5 AN XY: 725416

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000450

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hereditary spastic paraplegia 39 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Mar 10, 2023

For these reasons, this variant has been classified as Pathogenic. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt PNPLA6 protein function. ClinVar contains an entry for this variant (Variation ID: 854646). This missense change has been observed in individual(s) with clinical features of PNPLA6-related conditions (Invitae). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. It has also been observed to segregate with disease in related individuals. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces proline, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 261 of the PNPLA6 protein (p.Pro261Thr). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.77
BayesDel_addAF	Pathogenic	0.32	D
BayesDel_noAF	Pathogenic	0.22
CADD	Pathogenic	28
DANN	Uncertain	1.0
Eigen	Pathogenic	0.92
Eigen_PC	Pathogenic	0.84
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Pathogenic	0.98	.;D;D;D;D
M_CAP	Pathogenic	0.73	D
MetaRNN	Pathogenic	0.97	D;D;D;D;D
MetaSVM	Uncertain	0.24	D
PrimateAI	Uncertain	0.78	T
PROVEAN	Pathogenic	-7.4	D;D;D;D;.
REVEL	Pathogenic	0.68
Sift	Pathogenic	0.0	D;D;D;D;.
Sift4G	Uncertain	0.0030	D;D;D;D;D
Polyphen		1.0	D;.;.;D;.
Vest4		0.91
MutPred		0.80		.;.;.;.;Gain of helix (P = 0.0496);
MVP		0.70
MPC		2.4
ClinPred		1.0	D
GERP RS		5.4
Varity_R		0.83
gMVP		0.95

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

Publications

LitVar

Other links and lift over

dbSNP: rs1057518936; hg19: chr19-7605911;