chr16-86848-G-T

Variant names:

• chr16-86848-G-T
• rs189283988
• NM_001077350.3:c.1567C>A

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_001077350.3(NPRL3):​c.1567C>A​(p.Arg523Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,864 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R523H) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 34)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: NPRL3 NM_001077350.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.88
• Publications: 0 publications found

Genes affected

NPRL3 (HGNC:14124): (NPR3 like, GATOR1 complex subunit) Contributes to GTPase activator activity. Involved in cellular response to amino acid starvation and negative regulation of TOR signaling. Located in lysosomal membrane. Part of GATOR1 complex. Implicated in focal epilepsy. [provided by Alliance of Genome Resources, Apr 2022]

NPRL3 Gene-Disease associations (from GenCC):

• focal epilepsy

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• epilepsy, familial focal, with variable foci 3

  Inheritance: AD Classification: STRONG, MODERATE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
• familial focal epilepsy with variable foci

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NPRL3	NM_001077350.3	c.1567C>A	p.Arg523Ser	missense_variant	Exon 14 of 14	ENST00000611875.5	NP_001070818.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NPRL3	ENST00000611875.5	c.1567C>A	p.Arg523Ser	missense_variant	Exon 14 of 14	5	NM_001077350.3	ENSP00000478273.1

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460864 Hom.: 0 Cov.: 30 AF XY: 0.00 AC XY: 0 AN XY: 726660

African (AFR) AF: 0.00 AC: 0 AN: 33470

American (AMR) AF: 0.00 AC: 0 AN: 44666

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26122

East Asian (EAS) AF: 0.00 AC: 0 AN: 39680

South Asian (SAS) AF: 0.00 AC: 0 AN: 86130

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53058

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5750

European-Non Finnish (NFE) AF: 9.00e-7 AC: 1 AN: 1111656

Other (OTH) AF: 0.00 AC: 0 AN: 60332

GnomAD4 genome Cov.: 34

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Epilepsy, familial focal, with variable foci 3 Uncertain:1

Aug 31, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with serine, which is neutral and polar, at codon 523 of the NPRL3 protein (p.Arg523Ser). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with NPRL3-related conditions. ClinVar contains an entry for this variant (Variation ID: 1397088). 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 NPRL3 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	Benign	0.23
BayesDel_addAF	Pathogenic	0.47	D
BayesDel_noAF	Pathogenic	0.44
CADD	Pathogenic	29
DANN	Uncertain	0.99
DEOGEN2	Benign	0.16	T;.;T
Eigen	Uncertain	0.32
Eigen_PC	Uncertain	0.46
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.95	D;D;.
M_CAP	Benign	0.019	T
MetaRNN	Uncertain	0.43	T;T;T
MetaSVM	Benign	-0.92	T
PhyloP100		9.9
PrimateAI	Benign	0.44	T
REVEL	Uncertain	0.33
Sift4G	Benign	0.37	T;T;T
Polyphen		0.50	P;.;P
Vest4		0.45
MutPred		0.71		Loss of MoRF binding (P = 0.0548);.;Loss of MoRF binding (P = 0.0548);
MVP		0.48
MPC		0.30
ClinPred		0.99	D
GERP RS		5.4
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.89
gMVP		0.44
Mutation Taster		=73/27	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.050		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: rs189283988; hg19: chr16-136847;