chr8-19954168-G-T

Position:

• chr8-19954168-G-T

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PM1 PM2 PM5 PP3_Strong PP5_Moderate

The NM_000237.3(LPL):​c.590G>T​(p.Arg197Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000342 in 1,461,886 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 (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R197H) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: LPL NM_000237.3 missense
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 2.08

Genes affected

LPL (HGNC:6677): (lipoprotein lipase) LPL encodes lipoprotein lipase, which is expressed in heart, muscle, and adipose tissue. LPL functions as a homodimer, and has the dual functions of triglyceride hydrolase and ligand/bridging factor for receptor-mediated lipoprotein uptake. Severe mutations that cause LPL deficiency result in type I hyperlipoproteinemia, while less extreme mutations in LPL are linked to many disorders of lipoprotein metabolism. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Pathogenic. Variant got 12 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 5 uncertain in NM_000237.3
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr8-19954167-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 1471786.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.987
• PP5: Variant 8-19954168-G-T is Pathogenic according to our data. Variant chr8-19954168-G-T is described in ClinVar as [Pathogenic]. Clinvar id is 1452072.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
LPL	NM_000237.3	c.590G>T	p.Arg197Leu	missense_variant	5/10	ENST00000650287.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
LPL	ENST00000650287.1	c.590G>T	p.Arg197Leu	missense_variant	5/10		NM_000237.3	P1
LPL	ENST00000520959.5			downstream_gene_variant		4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251436 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135890

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000342 AC: 5 AN: 1461886 Hom.: 0 Cov.: 32 AF XY: 0.00000550 AC XY: 4 AN XY: 727246

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: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000270

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 32

ExAC AF: 0.00000824 AC: 1

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 20, 2022

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 LPL protein function. ClinVar contains an entry for this variant (Variation ID: 1452072). This variant is also known as R170L. This missense change has been observed in individual(s) with clinical features of chylomicronemia (PMID: 12839295, 25966443). This variant is present in population databases (rs372668179, gnomAD 0.0009%). This sequence change replaces arginine, which is basic and polar, with leucine, which is neutral and non-polar, at codon 197 of the LPL protein (p.Arg197Leu). This variant disrupts the p.Arg197 amino acid residue in LPL. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 25966443; Invitae). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.64
BayesDel_addAF	Pathogenic	0.44	D
BayesDel_noAF	Pathogenic	0.39
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.90	D;D
Eigen	Uncertain	0.66
Eigen_PC	Uncertain	0.63
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Uncertain	0.94	.;D
M_CAP	Pathogenic	0.70	D
MetaRNN	Pathogenic	0.99	D;D
MetaSVM	Pathogenic	0.96	D
MutationAssessor	Pathogenic	3.0	M;M
MutationTaster	Benign	0.96	D
PrimateAI	Uncertain	0.65	T
PROVEAN	Pathogenic	-5.5	D;.
REVEL	Pathogenic	0.67
Sift	Uncertain	0.0020	D;.
Sift4G	Uncertain	0.0060	D;.
Polyphen		0.97	D;D
Vest4		0.75
MutPred		0.93		Loss of disorder (P = 0.0696);Loss of disorder (P = 0.0696);
MVP		0.96
MPC		0.46
ClinPred		0.93	D
GERP RS		6.2
Varity_R		0.86
gMVP		0.96

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: rs372668179; hg19: chr8-19811679;