Metrics details. Despite some advances in recent years, the genetic control of gonadal sex differentiation during embryogenesis is still not completely understood. To identify new candidate genes involved in ovary and testis development, RNA-seq was used to define the transcriptome of embryonic chicken gonads at the onset of sexual differentiation day 6. RNA-seq revealed more than genes that were transcribed in a sex-biased manner at this early stage of gonadal differentiation.
Steroids - From Physiology to Clinical Medicine. Sex steroids are crucial hormones for the proper development and function of the body; they regulate sexual differentiation, the secondary sex characteristics, and sexual behavior patterns. Sex hormones production is sexually dimorphic, and involves differences not only in hormonal action but also in regulation and temporal patterns of production. Gonadal sex steroids effects are mediated by slow genomic mechanisms through nuclear receptors as well as by fast nongenomic mechanisms through membrane-associated receptors and signaling cascades. The term sex steroids is nearly always synonymous with sex hormones Wikipedia.
Identification of candidate gonadal sex differentiation genes in the chicken embryo using RNA-seq
Kulakov, Moscow, Russia. Gonadal differentiation has a determinative influence on sex development in human embryos. Disorders of sexual development DSD have been associated with persistent embryonal differentiation stages. Clinical investigations included karyotyping, ultrasound imaging, hormonal measurement and investigations of gonadal morphology.
A gonad, sex gland, or reproductive gland  is a mixed gland that produces the gametes sex cells and sex hormones of an organism. In the female of the species the reproductive cells are the egg cells , and in the male the reproductive cells are the sperm. The female gonad, the ovary , produces egg cells. Both of these gametes are haploid cells. The gonads are controlled by luteinizing hormone and follicle-stimulating hormone , produced and secreted by gonadotropes or gonadotrophins in the anterior pituitary gland.