rs1244234383

Variant names:

• chr19-7554577-G-C
• rs1244234383
• NM_001166114.2:c.2488G>C

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP2

The NM_001166114.2(PNPLA6):​c.2488G>C​(p.Gly830Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000197 in 152,178 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency: Genomes: 𝑓 0.000020 (0 hom., cov: 32)
• Consequence: PNPLA6 NM_001166114.2 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 3.44

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 Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the PNPLA6 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 29 curated pathogenic missense variants (we use a threshold of 10). The gene has 7 curated benign missense variants. Gene score misZ: 4.3547 (above the threshold of 3.09). Trascript score misZ: 3.5139 (above the threshold of 3.09). GenCC associations: The gene is linked to 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.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PNPLA6	NM_001166114.2	c.2488G>C	p.Gly830Arg	missense_variant	Exon 21 of 32	ENST00000600737.6	NP_001159586.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PNPLA6	ENST00000600737.6	c.2488G>C	p.Gly830Arg	missense_variant	Exon 21 of 32	1	NM_001166114.2	ENSP00000473211.1

Frequencies

GnomAD3 genomes AF: 0.0000197 AC: 3 AN: 152178 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000724

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: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome Cov.: 35

GnomAD4 genome AF: 0.0000197 AC: 3 AN: 152178 Hom.: 0 Cov.: 32 AF XY: 0.0000269 AC XY: 2 AN XY: 74332

Gnomad4 AFR AF: 0.0000724

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000113

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:2

Oct 04, 2019

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

In silico analysis, which includes protein predictors and evolutionary conservation, supports that this variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge; A different missense change at this residue (G792E) has been reported in the published literature (Synofzik et al., 2014) -

Oct 21, 2021

Mayo Clinic Laboratories, Mayo Clinic

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Hereditary spastic paraplegia 39 Uncertain:1

Nov 11, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 792 of the PNPLA6 protein (p.Gly792Arg). This variant is present in population databases (no rsID available, gnomAD 0.02%). This missense change has been observed in individual(s) with clinical features of hereditary spastic paraplegia (PMID: 34103343). ClinVar contains an entry for this variant (Variation ID: 537335). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt PNPLA6 protein function with a negative predictive value of 80%. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.94
BayesDel_addAF	Uncertain	0.061	T
BayesDel_noAF	Benign	-0.15
CADD	Pathogenic	26
DANN	Uncertain	0.99
Eigen	Benign	-0.096
Eigen_PC	Benign	-0.082
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.89	.;D;D;D;D
M_CAP	Uncertain	0.11	D
MetaRNN	Uncertain	0.64	D;D;D;D;D
MetaSVM	Benign	-1.0	T
PrimateAI	Uncertain	0.70	T
PROVEAN	Uncertain	-2.5	N;N;N;N;.
REVEL	Benign	0.26
Sift	Uncertain	0.0050	D;D;D;D;.
Sift4G	Uncertain	0.023	D;T;T;D;T
Polyphen		0.027	B;.;.;B;.
Vest4		0.75
MVP		0.40
MPC		1.2
ClinPred		0.92	D
GERP RS		3.6
Varity_R		0.26
gMVP		0.95

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

Publications

LitVar

Other links and lift over

dbSNP: rs1244234383; hg19: chr19-7619463;