The idea of such a phospholipid homeostasis was already proposed by Dorninger et al. (50) in 2015 by describing that the total sum of PE lipids (ester and ether) in fibroblasts of rhizomelic chondrodysplasia punctata patients as well as in brains of Gnpat-deficient mice was kept constant. This evidence concerns the gene GNPAT and rhizomelic chondrodysplasia punctata.