Studies on changes in the concentration of serum adrenal androgens in pubertal twins

Abstract

Abstract. A cross-sectional study was undertaken to investigate the correlation of the level of serum adrenal androgens with clinical signs of puberty and to assess the participation of genetic factors in the onset and progression of puberty. Serum concentrations of 11-deoxy-17-ketosteroids (11-deoxy-17-KS), dehydroepiandrosterone (DHEA) and androstenedione (4-A-dione) were measured in 74 monozygotic and 24 dizygotic twin pairs during the years of puberty. The mean serum concentrations of the adrenal androgens increased significantly with the advancement of bone age. A comparison of the adrenal androgen concentrations at a bone age of 15 years revealed the trend of earlier progression of puberty in girls than in boys. Serum 11-deoxy-17-KS and DHEA levels correlated fairly well with the stages of pubic and axillary hair growth in both sexes. No correlation of adrenal androgen levels with pituitary gonadotrophins or prolactin was observed in either sex during puberty. These results strongly suggest the importance of the specific action of adrenal androgens on the onset and progression of puberty, and further suggest that the maturation of the hypothalamic-pituitary-gonadal axis is not involved primarily in the maturation of the adrenal cortex during puberty. From the viewpoint of twin zygosity, intra-pair differences of serum adrenal androgen levels were compared between monozygotic and dizygotic pairs of twins. Serum 11-deoxy-17-KS and 4-A-dione levels in monozygotic pairs of twins showed a significantly higher intrapair similarity than in dizygotic pairs of twins. These findings suggest that during puberty the maturation of the adrenal cortex is regulated by genetic factors.