2-169127614-C-T

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2 BP4_Strong BS1_Supporting

The NM_004525.3(LRP2):c.*1049G>A variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00177 in 148,274 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.0018 (1 hom., cov: 32)
  • Exomes 𝑓: 0.0069 (0 hom.)
• Consequence: LRP2 NM_004525.3 3_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.673

Genes affected

LRP2 (HGNC:6694): (LDL receptor related protein 2) The protein encoded by this gene, low density lipoprotein-related protein 2 (LRP2) or megalin, is a multi-ligand endocytic receptor that is expressed in many different tissues but primarily in absorptive epithilial tissues such as the kidney. This glycoprotein has a large amino-terminal extracellular domain, a single transmembrane domain, and a short carboxy-terminal cytoplasmic tail. The extracellular ligand-binding-domains bind diverse macromolecules including albumin, apolipoproteins B and E, and lipoprotein lipase. The LRP2 protein is critical for the reuptake of numerous ligands, including lipoproteins, sterols, vitamin-binding proteins, and hormones. This protein also has a role in cell-signaling; extracellular ligands include parathyroid horomones and the morphogen sonic hedgehog while cytosolic ligands include MAP kinase scaffold proteins and JNK interacting proteins. Recycling of this membrane receptor is regulated by phosphorylation of its cytoplasmic domain. Mutations in this gene cause Donnai-Barrow syndrome (DBS) and facio-oculoacoustico-renal syndrome (FOAR).[provided by RefSeq, Aug 2009]

ACMG classification

Verdict is Likely_benign. Variant got -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.82).
• BS1: Variant frequency is greater than expected in population nfe. gnomad4 allele frequency = 0.00176 (260/147842) while in subpopulation NFE AF= 0.0032 (215/67230). AF 95% confidence interval is 0.00285. There are 1 homozygotes in gnomad4. There are 122 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
LRP2	NM_004525.3	c.*1049G>A		3_prime_UTR_variant	79/79	ENST00000649046.1
LRP2	XM_011511183.4	c.*1049G>A		3_prime_UTR_variant	78/78
LRP2	XM_011511184.3	c.*1049G>A		3_prime_UTR_variant	64/64
LRP2	XM_047444340.1	c.*1049G>A		3_prime_UTR_variant	79/79

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
LRP2	ENST00000649046.1	c.*1049G>A		3_prime_UTR_variant	79/79		NM_004525.3	P1

Frequencies

GnomAD3 genomes AF: 0.00176 AC: 260 AN: 147814 Hom.: 1 Cov.: 32

Gnomad AFR AF: 0.000525

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000336

Gnomad ASJ AF: 0.000580

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00160

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00320

Gnomad OTH AF: 0.000980

GnomAD4 exome AF: 0.00694 AC: 3 AN: 432 Hom.: 0 Cov.: 0 AF XY: 0.00769 AC XY: 2 AN XY: 260

Gnomad4 FIN exome AF: 0.00469

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.250

GnomAD4 genome AF: 0.00176 AC: 260 AN: 147842 Hom.: 1 Cov.: 32 AF XY: 0.00170 AC XY: 122 AN XY: 71858

Gnomad4 AFR AF: 0.000524

Gnomad4 AMR AF: 0.000336

Gnomad4 ASJ AF: 0.000580

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00160

Gnomad4 NFE AF: 0.00320

Gnomad4 OTH AF: 0.000975

Alfa AF: 0.00270 Hom.: 0

Bravo AF: 0.00145

Asia WGS AF: 0.000289 AC: 1 AN: 3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Donnai-Barrow syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.82
Cadd	Benign	3.2
Dann	Benign	0.56

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: rs528016062; hg19: chr2-169984124;