Cells of the zona fasciculata and zona reticularis lack aldosterone synthase (CYP11B2) that converts corticosterone to aldosterone, and thus these tissues produce only the weak mineralocorticoid corticosterone. However, both these zones do contain the CYP17A1 missing in zona glomerulosa and thus produce the major glucocorticoid, cortisol. Zona fasciculata and zona reticularis cells also contain CYP17A1, whose 17,20-lyase activity is responsible for producing the androgens, dehydroepiandrosterone (DHEA) and androstenedione. Thus, fasciculata and reticularis cells can make corticosteroids and the adrenal androgens, but not aldosterone.

The homeopaired box gene, Lim1 , appears to play a role in kidney and gonad development as targeted disruption of Lim1 results in mice lacking these organs. Lim1 is expressed in early urogenital ridge development in both the mesonephros and metanephros but its role in gonad development is not clear. The mouse gene M33 has also been implicated in gonad development. M33 shows similarity to the Drosophila polycomb group of genes ( PcG ). Mice carrying a disrupted M33 gene show retarded gonad development associated with varying degrees of XY sex reversal. In Drosophila , PcG proteins regulate the coordinate expression of homeotic genes. So it is possible that M33 may similarly regulate Hox gene expression in the mammalian urogenital ridge. Although SF1 , WT1 , Lim1 , and M33 all appear to be important in the formation of the indifferent gonad, their precise role is unknown.

The StAR protein was first identified, characterized and named by Dr. Douglas Stocco at Texas Tech University Health Sciences Center in 1994. [18] The role of this protein in lipoid CAH was confirmed the following year in collaboration with Dr. Walter Miller at the University of California, San Francisco . [19] All of this work follows the initial observations of the appearance of this protein and its phosphorylated form coincident with factors that caused steroid production by Dr. Nanette Orme-Johnson while at Tufts University . [20]