MRPL20

Chr 1

mitochondrial ribosomal protein L20

Also known as: L20mt, MRP-L20, bL20m

NCBI Gene: 55052ENSG00000242485UniProt: Q9BYC9

The protein is a component of the large 39S subunit of mitochondrial ribosomes, which synthesize proteins essential for mitochondrial function. Mutations cause autosomal recessive mitochondrial disorders affecting multiple organ systems, typically presenting in infancy or early childhood. This gene is highly constrained against loss-of-function variants, indicating that complete loss of protein function is likely incompatible with normal development.

Summary from RefSeq
Research Assistant →
0
Active trials
1
Pubs (1 yr)
136
P/LP submissions
0%
P/LP missense
1.82
LOEUF
DN
Mechanism· predicted
Clinical Summary— MRPL20
⚡
Population Constraint (gnomAD)
Low constraint (pLI 0.00) — loss-of-function variants are relatively tolerated in the population.
📋
ClinVar Variants
129 unique Pathogenic / Likely Pathogenic· 56 VUS of 195 total submissions
Explore recent and relevant literature in Research Assistant →

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

gnomAD
Tolerant — LoF & missense variants common in population
LoF Constraint
1.82LOEUF
pLI 0.000
Z-score -0.30
OE 1.12 (0.65–1.82)
Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint
-0.83Z-score
OE missense 1.25 (1.07–1.48)
105 obs / 83.7 exp
Tolerant

Tolerant to missense variation

Observed / Expected Ratios
LoF OE1.12 (0.65–1.82)
0≤0.351.4
Missense OE1.25 (1.07–1.48)
0≤0.61.4
Synonymous OE1.49
0≤1.21.6
LoF obs/exp: 8 / 7.1Missense obs/exp: 105 / 83.7Syn Z: -2.27
DN
0.6161th %ile
GOF
0.5071th %ile
LOF
0.3163th %ile

The highest-scoring mechanism for this gene is dominant-negative.

DNprediction above median

Note: In-silico variant effect predictors (SIFT, PolyPhen, REVEL, CADD) may underestimate pathogenicity of missense variants in genes with GOF or DN mechanisms. Consider functional evidence and clinical context.

Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312.

ClinVar Variant Classifications

195 submitted variants in ClinVar

ClinVar

Classification Summary

Pathogenic122
Likely Pathogenic7
VUS56
Likely Benign3
122
Pathogenic
7
Likely Pathogenic
56
VUS
3
Likely Benign

Curated Variants Distribution

Classified variants from ClinVar · 5 ACMG categories

ClassificationLoFMissense + InframeNon-codingSynonymousTotal
Pathogenic
0
0
122
0
122
Likely Pathogenic
0
0
7
0
7
VUS
0
37
19
0
56
Likely Benign
0
2
1
0
3
Benign
0
0
0
0
0
Total0391490188

LoF = frameshift, stop gained/lost, canonical splice · Counts from ClinVar esearch · Updated hourly

View in ClinVar →

Protein Context — Lollipop Plot

MRPL20 · protein map & ClinVar variants

Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

ClinicalTrials.gov

No active trials found for this gene.

Search ClinicalTrials.gov →
Clinical Literature
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Full-Text Mentions
NLP-detected gene mentions in article bodies · via PubTator3
PubTator3
Top 5 full-text resultsSearch PubTator3 ↗
Key Publications
Landmark & review papers · by relevance
PubMed
Top 2 results · since 2015Search PubMed ↗
Recent Gene-Specific Literature
Gene in title · MEDLINE · newest first
Europe PMC

No open access results found

Top 5 resultsSearch Europe PMC ↗

External Resources

Links to major genomics databases and tools

Franklin by Genoox
AI-powered variant curation and clinical analysis
DECIPHER
Genomic variants and phenotypes in rare disease patients