Variant Synonymizer: Platform to identify mutations defined in different ways is available now!

VarSy

Over 2,000 gene–disease validation summaries are now available—no login required!

Browse Summaries

PARS2 – Mitochondrial Disease

PARS2 (prolyl-tRNA synthetase 2) deficiency is associated with autosomal recessive mitochondrial disease (MONDO:0044970). Biallelic PARS2 variants were identified by whole-exome sequencing in three unrelated probands with clinical features of mitochondrial dysfunction. In a cohort of 113 pediatric patients, a novel PARS2 missense variant c.239T>C (p.Ile80Thr) was detected (PMID:27290639). Independent reports described a patient with coagulation factor abnormalities and global developmental delay carrying c.1091C>G (p.Pro364Arg) (PMID:32071833) and a lethal mitochondrial cardiomyopathy case with c.283G>A (p.Val95Ile) (PMID:39253392). All patients presented early-onset symptoms and biochemical evidence of impaired oxidative phosphorylation; segregation analysis confirmed compound heterozygosity under an autosomal recessive model.

Functional data are limited but suggest loss of prolyl-tRNA ligase activity leading to defective mitochondrial translation. Published studies report nonspecific metabolic perturbations and variable MRI findings, without cellular or animal model validation or rescue experiments. Thus, current evidence supports a Limited clinical validity per ClinGen: PARS2 variants are recurrent in AR cases, but larger cohorts and mechanistic assays are lacking. Additional functional and model organism studies are warranted. Key take-home: Include PARS2 in genetic panels for autosomal recessive pediatric mitochondrial presentations.

References

  • Journal of translational medicine • 2016 • New perspective in diagnostics of mitochondrial disorders: two years' experience with whole-exome sequencing at a national paediatric centre. PMID:27290639
  • JIMD reports • 2020 • Phenotypes and genotypes of mitochondrial aminoacyl-tRNA synthetase deficiencies from a single neurometabolic clinic. PMID:32071833
  • Frontiers in cardiovascular medicine • 2024 • Case Report: Lethal mitochondrial cardiomyopathy linked to a compound heterozygous variant of PARS2. PMID:39253392

Evidence Based Scoring (AI generated)

Gene–Disease Association

Limited

3 unrelated probands with biallelic PARS2 variants (PMID:27290639; PMID:32071833; PMID:39253392)

Genetic Evidence

Limited

Three AR probands with compound heterozygous missense PARS2 variants

Functional Evidence

Limited

Predicted loss of enzymatic activity without cellular/animal model or rescue data