Endocrine Abstracts

Objective: In the marmoset (Callithrix jacchus) the LH is functionally replaced by the chorionic gonadotropin (CG). However, disparate to the human LH/hCG system, marmoset CG is expressed in both, the pituitary and in the placenta. Previously, we could show the presence of a tissue-specific promoter system in the marmoset. Alternative promoters, as well as different first exons, either a pituitary or a novel placenta specific one, are being employed to direct tissue spe...

Introduction: FSH is a key player in reproductive functions, the expression of its unique subunit FSHB is regulated by the FSHB promoter. Recently, a single nucleotide polymorphism (SNP) at a highly conserved position in the FSHB promoter (rs10835638; −211G>T) has been found to be associated with decreased serum FSH levels in men and with male infertility. Because to date no information is available on possible endocrine consequences of this SNP in women, we conducte...

Objective: The LH and chorionic gonadotropin (CG) are essential for reproduction and male sexual development. While LH induces tesosterone production, CG is essential for the establishment of pregnancy. In the New World Monkeys (NWM) the initial duplication of the ancestral LH-beta subunit (LHB) gene, which gave rise to the novel CG-beta subunit (CGB) gene, was followed by a genomic rearrangement event, leading to CGB expression in pituitary and placenta, whereas LHB became a ...

Testosterone is the hormone that turns males into men and a lack of testosterone, whether of primary or secondary origin, causes hypogonadism characterized by lack of pubertal development or loss of maleness. It was generally assumed that in a man with a normal androgen receptor (AR) androgenicity is regulated by testosterone serum concentrations, slightly modified by SHBG. Only recently it became evident that variations in the AR gene influence testosterone action. Modulation...

Background: Klinefelter syndrome (KS) is the most frequent genetic cause of male infertility. Individuals share the endocrine hallmark of hypergonadotropic hypogonadism, displaying high gonadotropin levels due to deficient testicular function. A single-nucleotide polymorphism (SNP) located within the FSHB promoter region (−211G>T, rs10835638) was recently shown to be associated with reduced serum FSH levels and other reproductive parameters in men. The objec...

Background: Recently, a single nucleotide polymorphism (SNP) in the FSHB promoter (−211G>T, rs10835638) was found to be associated with lower serum FSH levels and oligozoospermia in males. In contrast, a SNP in the FSH-receptor gene (FSHR, 2039A>G, rs6166) was previously shown to be associated with FSH levels in women only.Subjects and methods: One thousand two hundred and thirteen male partners in infertile couples without known c...

Objectives: Male pseudohermaphroditism, or Leydig cell hypoplasia (LCH), is an autosomal recessive disorder in individuals with a 46, XY karyotype, characterized by a predominantly female phenotype despite the presence of testicular structures. It is caused by mutations in the luteinizing hormone/chorionic gonadotropin receptor gene (LHCGR), which impair either LH/CG binding or signal transduction. However, molecular analysis has revealed that the LHCGR is apparently normal in...

Male sexual development and masculinization are triggered by two hormones, CG and LH. While CG, produced by the trophoblasts during pregnancy, is essential for normal development of male secondary sex organs, pituitary LH is indispensable for virilization and initiation and maintenance of spermatogenesis. Both hormones exert their action via the LH receptor (LHR) expressed in the Leydig cells by stimulating testosterone biosynthesis. This two hormone/one receptor system is exc...

Background: The LHR is a crucial mediator for normal sexual development and fertility. In the marmoset monkey (Callithrix jacchus), LHR type II, lacking exon 10, is the native receptor type. In addition to the testis, the LHR is expressed in the adrenal gland where its function remains unknown.Aim: To characterise marmoset LHR expression at different stages of puberty in the testis and adrenal gland and examine different splice variants in the tes...

Background: The rare 46, XX-male syndrome has to be distinguished from more frequent forms of hypogonadism, especially the Klinefelter syndrome (47, XXY). We report 11 cases of SRY-positive XX-males in comparison to 101 age-matched Klinefelter patients and 78 age-matched normal men in a case-control study.Methods: The comparison included results from the physical examination, endocrinological data, semen analysis, cytogenetic and molecular genetic findin...