3-190388154-GT-G

Position:

• chr3-190388154-GT-G

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The ENST00000456423.2(CLDN16):​c.-173del variant causes a 5 prime UTR change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: CLDN16 ENST00000456423.2 5_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.66

Genes affected

CLDN16 (HGNC:2037): (claudin 16) Tight junctions represent one mode of cell-to-cell adhesion in epithelial or endothelial cell sheets, forming continuous seals around cells and serving as a physical barrier to prevent solutes and water from passing freely through the paracellular space. These junctions are comprised of sets of continuous networking strands in the outwardly facing cytoplasmic leaflet, with complementary grooves in the inwardly facing extracytoplasmic leaflet. The protein encoded by this gene, a member of the claudin family, is an integral membrane protein and a component of tight junction strands. It is found primarily in the kidneys, specifically in the thick ascending limb of Henle, where it acts as either an intercellular pore or ion concentration sensor to regulate the paracellular resorption of magnesium ions. Defects in this gene are a cause of primary hypomagnesemia, which is characterized by massive renal magnesium wasting with hypomagnesemia and hypercalciuria, resulting in nephrocalcinosis and renal failure. This gene and the CLDN1 gene are clustered on chromosome 3q28. [provided by RefSeq, Jun 2010]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

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

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CLDN16	NM_001378492.1	c.-93-80del		intron_variant			NP_001365421.1
CLDN16	NM_001378493.1	c.-93-80del		intron_variant			NP_001365422.1
CLDN16	XM_047447333.1	c.-93-80del		intron_variant			XP_047303289.1
CLDN16	NM_006580.4			upstream_gene_variant		ENST00000264734.3	NP_006571.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CLDN16	ENST00000456423.2	c.-173del		5_prime_UTR_variant	1/2	1		ENSP00000414136
CLDN16	ENST00000468220.1	n.306+13554del		intron_variant, non_coding_transcript_variant		4
CLDN16	ENST00000264734.3			upstream_gene_variant		1	NM_006580.4	ENSP00000264734	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Primary hypomagnesemia Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Apr 27, 2017

The CLDN16 c.38delT (p.Leu13CysfsTer15) variant causes a frameshift, and is predicted to result in premature termination of the protein. A literature search was performed for the gene, cDNA change, and amino acid change. No publications were found based on this search. This variant is not found in the 1000 Genomes Project, the Exome Sequencing Project, or the Exome Aggregation Consortium. Based on the variant frequency, disease prevalence, disease penetrance, and inheritance mode, this variant could not be ruled out of causing disease. Due to the potential impact of frameshift variants and the lack of clarifying evidence, this variant is classified as a variant of unknown significance but suspicious for pathogenicity for primary hypomagnesemia. This variant was observed by ICSL as part of a predisposition screen in an ostensibly healthy population. -

Computational scores

Source: dbNSFP v4.3

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: rs886058244; hg19: chr3-190105943;