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A major component of variation in body height is due to genetic differences, but environmental factors have a substantial contributory effect. In this study we aimed to analyse whether the genetic architecture of body height varies between affluent western societies. We analysed twin data from eight countries comprising 30,111 complete twin pairs by using(More)
The process of germ cell depletion in patients with Klinefelter syndrome (KS) is incompletely characterized. In the current work, we evaluated the presence of germ cells in adolescent boys with KS for possible future use in assisted reproduction techniques. Fourteen nonmosaic 47,XXY boys (aged 10-14 yr) were enrolled. Every fourth month their puberty was(More)
GATA-4 is a highly conserved transcription factor that plays a critical role in regulating embryonic morphogenesis and cellular differentiation. Given the emerging role of GATA-4 in the development and function of murine gonads, we have now studied its role in human testis. We find that GATA-4 is expressed from early human fetal testicular development to(More)
Determinations of serum gonadotropin concentrations by ultra-sensitive methods have improved the diagnosis of pubertal disorders. The onset of puberty can be estimated by measuring serum gonadotropin pulsation, but as this requires serial nocturnal blood sampling, it is not a routine investigation. Gonadotropin measurements in first morning voided (FMV)(More)
During the human menstrual cycle the circulating levels of inhibin B, a dimer of inhibin alpha- and beta(B)-subunits, fluctuate in a fashion distinct from that of inhibin A, the alpha-beta(A)-subunit dimer. This suggests that human inhibin subunits are each regulated in a distinct manner in human ovarian granulosa cells by endocrine and local factors. We(More)
Congenital hypogonadotropic hypogonadism (CHH) is a rare disorder caused by the deficient production, secretion or action of gonadotropin-releasing hormone (GnRH), which is the master hormone regulating the reproductive axis. CHH is clinically and genetically heterogeneous, with >25 different causal genes identified to date. Clinically, the disorder is(More)
Whether children, especially girls, are entering and progressing through puberty earlier today than in the mid-1900s has been debated. Secular trend analysis, based on available data, is limited by data comparability among studies in different populations, in different periods of time, and using different methods. As a result, conclusions from data(More)
The necessity of estrogens for male fertility was recently discovered in studies on both estrogen receptor alpha knockout and aromatase (cyp 19 gene) knockout mice. However, direct testicular effects of estrogens in male reproduction have remained unclear. Here we studied the protein expression of ERalpha and the recently described estrogen receptor beta in(More)
CONTEXT Postnatal pituitary-testicular activation in infant boys is well characterized. However, the ovarian response to pituitary activation in infancy is less well understood. OBJECTIVE The aim of the study was to compare postnatal developmental changes in the pituitary-ovarian axis in preterm and term infant girls. PARTICIPANTS AND DESIGN Sixty-three(More)
Glucocorticoids rate among the most controversial topics in today's perinatology and neonatology. Many sick preterm infants exhibit signs of adrenal insufficiency, the etiology, diagnostic criteria, and optimal treatment of which are under debate. Moreover, most of these infants are exposed to pharmacological glucocorticoid doses both in utero and after(More)