Developmental Genetics of the External Genitalia

  • Martin J. Cohn
Conference paper
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 545)


The incidence of congenital malformation of the urogenital system is second only to that of the cardiovascular system, yet comparatively little is known about the cellular and molecular mechanisms that regulate urogenital organogenesis. In this chapter, I review recent advances in the developmental biology of the external genitalia, and discuss the implications of this work for our understanding of hypospadias. The majority of research into external genital development and hypospadias has focused on the endocrine system, particularly on the role of androgens (see accompanying chapters in this volume). A relatively unexplored area of genital morphogenesis is the early, genetically controlled process of pattern formation, when genital tubercle outgrowth and three-dimensional patterning occurs (Figure 1). These processes occur in the absence of endocrine signals, and identification of the molecular mechanisms of early genital development is crucial to our understanding of congenital anomalies.


External Genitalia Apical Ectodermal Ridge Urethral Plate Androgen Signaling Genital Development 
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Copyright information

© Springer Science+Business Media New York 2004

Authors and Affiliations

  • Martin J. Cohn
    • 1
  1. 1.Department of ZoologyUniversity of FloridaGainesville

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