DEVELOPMENTS IN SEXUAL ORGANOGENESIS
313
teleost, 0. latipes, has been established as a result of studying crosses of
individuals of sexually reversed phenotype.
The tendency to return to the genetic sex after deviation of sexual differentiation owing to the epigenetic effect of exogenous steroid hormones
shows the stability of genie action in the course of the life of the individual.
Sexual differentiation is not linked to the genetic structure of the germ
cells themselves, but to inductive effects emanating from the embryonic
areas where the germ cells are located.
C. Biosynthesis of Steroids in the Embryonic Phases
of Sexual Differentiation
Biochemical studies undertaken in vertebrates, analysis of the biosynthesis and the metabolism of steroid hormones in larvae and fetuses, demonstration of active enzyme systems at very early stages of development—all
these are very active research areas at the present time. They tend to
establish the decisive role of the steroids from the beginning of sexual
organogenesis.
Control by genetic and epigenetic factors has been considered separately
for a long time. In fact, current trends in research attest to a continuing
relationship between these two groups of factors throughout the life of the
organism. Genie action always seems able to manifest itself. Thus the
problem is set forth, at the cellular level, as one concerning the epigenetic
actions, particularly of the steroids in the vertebrates, on the functioning
of the sexualizing genes.
References
Acevedo, H. F., Axelrod, L. R., Ishikawa, E., and Takaki, F. (1963). /. Clin. Endocnnol. Me tab. 23, 885.
Allen, E., ed. (1934). "Sex and Internal Secretions," Vol. I. Williams & Wilkins,
Baltimore, Maryland; Baillière, London.
Allen, E., ed. (1939). "Sex and Internal Secretions," Vol. II. Williams & Wilkins,
Baltimore, Maryland; Baillière, London.
Aida, T. (1921). On the inheritance of color in a fresh water fish, Aplocheilus latipes
Temmick and Schlegel, with special reference to sex linked inheritance. Genetics
6, 554.
Armstrong, C. N. (1964). In "Intersexuality in Vertebrates including Man" (C. N.
Armstrong and A. J. Marshall, eds.), Chapt. 8, pp. 349-393. Academic Press,
New York.
Armstrong, C. N., and Marshall, A. J., eds. (1964). "Intersexuality in Vertebrates
Including Man." Academic Press, New York.
Bacci, G. (1965). "Sex Determination." Macmillan (Pergamon), New York.
Baltzer, F. (1914). Mitt. Zool. Staz.-Neapel 22, 1.
Beatty, R. A. (1957). Monograph Exptl. Biol. 7. Cambridge Univ. Press, London and
New York.
Beatty, R. A. (1964). In "Intersexuality in Vertebrates including Man" (C. N. Armstrong and A. J. Marshall, eds.), Chapt. 2, pp. 17-143. Academic Press, New York.
313
teleost, 0. latipes, has been established as a result of studying crosses of
individuals of sexually reversed phenotype.
The tendency to return to the genetic sex after deviation of sexual differentiation owing to the epigenetic effect of exogenous steroid hormones
shows the stability of genie action in the course of the life of the individual.
Sexual differentiation is not linked to the genetic structure of the germ
cells themselves, but to inductive effects emanating from the embryonic
areas where the germ cells are located.
C. Biosynthesis of Steroids in the Embryonic Phases
of Sexual Differentiation
Biochemical studies undertaken in vertebrates, analysis of the biosynthesis and the metabolism of steroid hormones in larvae and fetuses, demonstration of active enzyme systems at very early stages of development—all
these are very active research areas at the present time. They tend to
establish the decisive role of the steroids from the beginning of sexual
organogenesis.
Control by genetic and epigenetic factors has been considered separately
for a long time. In fact, current trends in research attest to a continuing
relationship between these two groups of factors throughout the life of the
organism. Genie action always seems able to manifest itself. Thus the
problem is set forth, at the cellular level, as one concerning the epigenetic
actions, particularly of the steroids in the vertebrates, on the functioning
of the sexualizing genes.
References
Acevedo, H. F., Axelrod, L. R., Ishikawa, E., and Takaki, F. (1963). /. Clin. Endocnnol. Me tab. 23, 885.
Allen, E., ed. (1934). "Sex and Internal Secretions," Vol. I. Williams & Wilkins,
Baltimore, Maryland; Baillière, London.
Allen, E., ed. (1939). "Sex and Internal Secretions," Vol. II. Williams & Wilkins,
Baltimore, Maryland; Baillière, London.
Aida, T. (1921). On the inheritance of color in a fresh water fish, Aplocheilus latipes
Temmick and Schlegel, with special reference to sex linked inheritance. Genetics
6, 554.
Armstrong, C. N. (1964). In "Intersexuality in Vertebrates including Man" (C. N.
Armstrong and A. J. Marshall, eds.), Chapt. 8, pp. 349-393. Academic Press,
New York.
Armstrong, C. N., and Marshall, A. J., eds. (1964). "Intersexuality in Vertebrates
Including Man." Academic Press, New York.
Bacci, G. (1965). "Sex Determination." Macmillan (Pergamon), New York.
Baltzer, F. (1914). Mitt. Zool. Staz.-Neapel 22, 1.
Beatty, R. A. (1957). Monograph Exptl. Biol. 7. Cambridge Univ. Press, London and
New York.
Beatty, R. A. (1964). In "Intersexuality in Vertebrates including Man" (C. N. Armstrong and A. J. Marshall, eds.), Chapt. 2, pp. 17-143. Academic Press, New York.