Development of the endocrine system of gestation, somatotroph cells begin to develop with cytoplasmic expression of human growth hormone. Once a fetus reaches 12 weeks of development, the thyrotrophs begin expression of Beta subunits for TSH, while gonadotrophs being to express beta-subunits for LH and FSH. Male fetuses predominately produced LH-expressing gonadotrophs, while female fetuses produce an equal expression of LH and FSH expressing gonadotrophs. At 24 weeks of gestation, prolactin-expressing lactotrophs begin to emerge. Development of the endocrine system The fetal endocrine system is one of the first systems to develop during prenatal development. The fetal adrenal cortex can be identified within four weeks
Multiple endocrine neoplasia 40 years of age. There is significant intra- and inter-familial variability in the age of onset, severity of disease, and tumor types. Despite numerous studies, no genotype-phenotype correlations have been established, suggesting that unknown genetic and environmental modifiers are involved in the expression of the MEN1 phenotype. Multiple Endocrine Neoplasia type 1 (MEN1) is a rare hereditary endocrine cancer syndrome characterized primarily by tumors of the parathyroid glands (95% of cases), endocrine gastroenteropancreatic (GEP) tract (30-80% of cases), and anterior pituitary (15-90% of cases). Other endocrine and non-endocrine neoplasms including adrenocortical and thyroid tumors, visceral and cutaneous lipomas, meningiomas, facial