KDELR2

Chr 7

KDEL endoplasmic reticulum protein retention receptor 2

Also known as: ELP-1, ERD2.2, OI21

NCBI Gene: 11014 ENSG00000136240 UniProt: P33947

Retention of resident soluble proteins in the lumen of the endoplasmic reticulum (ER) is achieved in both yeast and animal cells by their continual retrieval from the cis-Golgi, or a pre-Golgi compartment. Sorting of these proteins is dependent on a C-terminal tetrapeptide signal, usually lys-asp-glu-leu (KDEL) in animal cells, and his-asp-glu-leu (HDEL) in S. cerevisiae. This process is mediated by a receptor that recognizes, and binds the tetrapeptide-containing protein, and returns it to the ER. In yeast, the sorting receptor encoded by a single gene, ERD2, is a seven-transmembrane protein. Unlike yeast, several human homologs of the ERD2 gene, constituting the KDEL receptor gene family, have been described. KDELR2 was the second member of the family to be identified, and it encodes a protein which is 83% identical to the KDELR1 gene product. Alternative splicing results in multiple transcript variants encoding distinct isoforms. [provided by RefSeq, Jul 2008]

Primary Disease Associations & Inheritance

UniProtOsteogenesis imperfecta 21

ClinVar variants

Pathogenic / LP

0.17

pLI score

Active trials

Clinical Summary— KDELR2

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Population Constraint (gnomAD)

Constrained for loss-of-function variants (OE-LoF 0.29) despite low pLI — interpret in context.

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ClinVar Variants

37 Pathogenic / Likely Pathogenic· 46 VUS of 92 total submissions

Some data sources returned errors (1)

omim: Error: OMIM fetch failed: 429

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

gnomAD

Tolerant — LoF & missense variants common in population

LoF Constraint?LOEUF (Loss-of-function Observed/Expected Upper bound Fraction) is the upper bound of the 90% CI for LoF OE — the preferred gnomAD v4 metric. Lower = more intolerant to LoF. LOEUF < 0.35 = highly constrained.

0.74LOEUF

pLI 0.167

Z-score 2.15

OE 0.29 (0.13–0.74)

Tolerant

Typical tolerance to LoF variation

Missense Constraint?Missense Z-score: standard deviations fewer missense variants observed vs. expected. Z > 3.09 (p < 0.001) = gene does not tolerate missense variation. OE missense < 0.6 is also considered constrained.

0.80Z-score

OE missense 0.79 (0.67–0.94)

91 obs / 115.3 exp

Tolerant

Mild missense constraint

Observed / Expected Ratios?Shaded band = 90% confidence interval. Vertical tick = point estimate. Grey threshold line = gnomAD constraint cutoff for that variant class.

LoF OE?Ratio of observed to expected LoF variants. Upper CI bound (LOEUF) ≤ 0.35 = strong LoF constraint signal.0.29 (0.13–0.74)

0≤0.351.4

Missense OE?Ratio of observed to expected missense variants. OE ≤ 0.6 = fewer missense variants than expected by chance.0.79 (0.67–0.94)

0≤0.61.4

Synonymous OE?Control metric — synonymous variants are largely neutral and expected near OE = 1.0. Significant deviation may indicate annotation issues.1.04

0≤1.21.6

LoF obs/exp: 3 / 10.5Missense obs/exp: 91 / 115.3Syn Z: -0.19