Research study in boys and young men with X-linked ichthyosis on hormones and puberty Researchers from the University of Birmingham and the Birmingham Children’s Hospital NHS Trust have undertaken a study in boys and young men with X-linked ichthyosis (XLI) which has recently been published in a medical journal ( details below1). The study was greatly supported by the ISG: most of the people who volunteered to take part did so after seeing information sent out by ISG. XLI is caused by the lack of an enzyme called steroid sulphatase (STS). The same enzyme is involved in processing male hormones (androgens). So the researchers wanted to check whether androgens function normally in people with XLI. Androgens have a several functions in males, in particular during puberty like development of the sexual organs and the growth spurt. Volunteers with XLI were asked to attend a research clinic at the Birmingham Children’s Hospital (children below 16 years of age) and at the University Hospital Birmingham (young men older than 16 years) where they were seen by an endocrinologist (hormone doctor). For each person with XLI at least one volunteer without the condition of the same age was recruited to compare the study results (‘control group’). Each study participant was asked to provide a urine sample (collected over 24 hours) and a blood sample. The samples were sent to the research laboratory at the University of Birmingham where steroid hormones were measured with state-of-the-art mass spectrometry techniques. The results from people with XLI were compared to those from the control group. The researchers found that some androgens are lower in people with XLI due to their lack of STS, but remarkably it does not affect their development and progression through puberty. The explanation seems to be partly that people with XLI had higher activities of a different enzyme (5alpha-reductase), which activates androgens. In other words, the body seems to be able to compensate for reduced androgen production due to deficiency of STS by finding a way to increase androgen activity. Overall, this study reveals important novel insights into the function of the STS enzyme. Overall, this study provides important insights for patients with XLI, as the condition does not seem to affect their development during puberty and beyond. In addition, this study helps to understand how the enzyme STS works ‘in real life’ and future studies are planned to learn more about how the STS enzyme is regulated. The research team is greatly indebted to all study participants and to ISG for their support. The full text publication can be downloaded for free from the journal website by following this link: http://press.endocrine.org/doi/10.1210/jc.2015-4101?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub%3dpubmed Idkowiak J, Taylor AE, Subtil S, O’Neil DM, Vijzelaar R, Dias RP, Amin R, Barrett TG, Shackleton CHL, Kirk JMW, Moss C, Arlt W. Steroid Sulfatase Deficiency and Androgen Activation Before and After Puberty. J Clin Endocrinol Metab 2016;101(6):2545–2553. doi:10.1210/jc.2015-4101.