BACKGROUND: Glycyl-tRNA synthetase (GARS) is an aminoacyl-tRNA synthetase (ARS) 
that links the amino acid glycine to its corresponding tRNA prior to protein 
translation and is one of three bifunctional ARS that are active within both the 
cytoplasm and mitochondria. Dominant mutations in GARS cause rare forms of 
Charcot-Marie-Tooth disease and distal spinal muscular atrophy.
CASE PRESENTATION: We report a 12-year old girl who presented with clinical and 
biochemical features of a systemic mitochondrial disease including 
exercise-induced myalgia, non-compaction cardiomyopathy, persistent elevation of 
blood lactate and alanine and MRI evidence of mild periventricular leukomalacia. 
Using exome sequencing she was found to harbor compound heterozygous mutations 
within the glycyl-tRNA synthetase (GARS) gene; c.1904C > T; p.Ser635Leu and 
c.1787G > A; p.Arg596Gln. Each mutation occurred at a highly conserved site 
within the anticodon binding domain.
CONCLUSION: Our findings suggest that recessive mutations in GARS may cause 
systemic mitochondrial disease. This phenotype is distinct from patients with 
previously reported dominant mutations in this gene, thereby expanding the 
spectrum of disease associated with GARS dysregulation.