This suggests a specific constellation of clinical traits linked to mutations at the COQ5 locus, so far, encompassing cerebellar ataxia, encephalopathy, developmental delay, short stature, dysarthria, ID, cerebellar atrophy, and COQ10 deficiency in leucocyte assay (Table 1: 2, 3, 5, 6, 9, 10, 29, 55, respectively). The gene discussed is COQ5; the disease is Global developmental delay.