Research Interests

As a biomedical investigator in pediatric endocrinology, my work has focused on the genetic, hormonal, and phenotypic characterization of congenital adrenal hyperplasia (CAH), a term describing a family of monogenic autosomal recessive disorders of steroidogenesis in which enzymatic defects result in impaired synthesis of cortisol by the adrenal cortex. Treatment and prevention has also been devised. The most common type of CAH is 21-hydroxylase deficiency, which occurs in a classical form that causes genital ambiguity at birth in genetic female and post-natal virilization in males and females. A milder, nonclassical form occurs without genital ambiguity and it is the most frequent autosomal recessive genetic defect in man. My genetic research on the mutations that cause CAH led to the ability to diagnose fetuses through DNA testing, thus for the first time enabling prenatal treatment that can prevent genital ambiguity in the female, and thus, wrong sex assignment and its traumatic psychological consequences. In addition, I have discovered a new form of hypertension, termed apparent mineralocorticoid excess (AME), which has opened a new field of receptor biology. In 1995, we described the first mutation in the HSD11B2 gene in a patient with AME. My team also first described dexamethasone suppressible hyperaldosteronism, another form of low-renin hypertension. When CAH and AME patients are divided into mutation-identical groups, the phenotype does not always match the genotype. At this time, we know of no mechanism to explain this nonconformity, which we continue to explore.

Membership Type

Emeritus

Election Year

1996

Primary Section

Section 42: Medical Physiology and Metabolism