Vle CONG. INTERN. REPROD. ANIM. INSEM. ARTIF., PARIS, 1968, VOL. II

ASPECTS OF INTERSEXUALITY IN DOMESTIC MAMMALS

Department of Population and Family Health
Division of Population Dynamics

Johns Hopkins School of Hygiene and Public Health
Baltimore, Maryland, 21205, U.S.A.

J.D. Biggers

INTRODUCTION

Intersexuality has interested man since ancient times,
and as a result, a very large literature about it has accumulated.
Several monographs deal with the subject, for example Overzier,
(1963) and Armstrong and Marshall (1964). In recent years there
has been a resurgence of interest in the field because ofarevos
lutionary developments in cytogenetics. I wish to discuss the
impact of these developments on the study of intersexuality in
domestic mammals.

The discovery that the genetic sex of individual cats
could be diagnosed by the presence or absence of nuclear sex
chromatin (Barr and Bertram, 1949) was rapidly applied to the
study of clinical human intersexual conditions. These studies
revealed that Turner's and Klinefelter's syndromes are associa-
ted with aberrations of the genetic sex. Ten years after the
discovery of sex chromatin Lejeune, Gautier and Turpin (1959)
showed that some cases of Down's syndrome in man are associated
with trisomy of the 21lst pair of autosomes. Soon afterwards
it was shown that Turner's and Klinefelter's syndromes had XO
and XXY karyotypes respectively. The clinical significance of
the fact that many individuals with abnormal karyotypes may die

in utero has only been appreciated since Carr (1963) studied

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