Mitochondrial respiratory chain complex assembly and function during human fetal development.

Oxidative phosphorylation (OXPHOS) deficiency may have early antenatal manifestations, probably related to the time course and/or tissue specificity of the disease gene expression during the embryo-fetal period. This feature hampers a fully reliable prenatal enzymological diagnosis of OXPHOS deficiency. We have studied OXPHOS in various human fetal tissues from 9 to 17 weeks of gestation.