The Variety of Vertebrate Mechanisms of Sex Determination

Table 2

Mechanisms of sex determination and experimental sex reversal in vertebrates (adopted from [13]).

Mechanism of sex determination	Species	Effectors	Experimental evidence of sex reversal
TSD (t°C)	American alligator and Red-eared slider turtle	Aromatase or Estradiol (E2)	F-M: administration of an aromatase inhibitor introduced at F-producing temperatures; M-F: E2 administration to eggs incubated at male-producing temperatures
GSD (XX/XY; ZZ/ZW)	Oryzias latipes, Bufo bufo, and  Xenopus laevis	Androgene or; E2	—
GSD; (ZZ/ZW)	Gallus gallus	Aromatase or Estradiol (E2)	F-M: in ovo administration of an aromatase inhibitor to ZW animals; M-F: in ovo administration of E2 to ZZ individuals
GSD (XX/XY)	Macropus eugenii and Mus musculus	Sry	F-M: treatment of XX individuals with Müllerian inhibiting substance (MIS) to cause germ loss, addition of Sry gene in XX embryos; loss of E2 through ERα 𝛽KO causes transdifferentiation of the ovary to testis-like structures in the adult; M-F: inactivation of Sry gene in XY embryos, E2 administration to XY

Here: F: female, M: male, E₂: estrogene, X, Y, Z, W: sex chromosomes.