The involvement of cytochrome B5 in 16-androstene steroid synthesis in pig testis



Davis, Shawn Marit

Journal Title

Journal ISSN

Volume Title


University of Guelph


A primary cause of boar taint are the 16-androstene steroids. Identification of factors linked to 16-androstene steroid synthesis may provide a means to identify and select untainted boars for use in pork production. Cytochrome b\sb5, was previously shown to be essential for formation of 16-androstene steroids, but not androgens, in porcine testis in vitro. High and low molecular weight isoforms of cytochrome b\sb5 were identified in testis by Western blotting and RT-PCR. We have found a correlation between the rate of testicular 16-androstene steroidogenesis, concentrations of 16-androstene steroid in fat and levels of the low molecular weight isoform of cytochrome b\sb5, in testis in vivo. Levels of total cytochrome b\sb5 mRNA in testis were also correlated with levels of 16-androstene steroid in fat. Full characterization of the two isoforms of cytochrome b\sb5 in porcine testis is now necessary. The low molecular weight isoform may represent a unique factor linked to 16-androstene steroid synthesis and may be used in the identification and selection of untainted boars.



boar taint, 16-androstene steroids, synthesis, pork production, cytochrome B5, porcine testis