In addition to genes involved in Q synthesis, we found homologues for two genes linked to human mitochondrial complex I deficiency (OMIM 252010), ND75 (NDUFS1) and l(2)37Bb (FOXRED1) to genetically interact with DmManf. Considering all our data indicating a mitochondrial function, DmManf could affect the oxidative phosphorylation, directly or indirectly. The gene discussed is NDUFS1; the disease is hyperinsulinemic hypoglycemia, familial, 4.