Spontaneous sexual development in a chromatin negative female with XO blood leukocyte karyotype.

Although Turner's syndrome is usually associated with a spectrum of phenotypic abnormalities, the relatively constant features are short stature and the absence of breast development, menstruation, and fertility. An unusual exception to this general prognosis was the case reported by Bahner, et al.1,2 Their patient had short stature and a low occipital hairline; she was chromatin negative and karyotypically XO in cultures of bone marrow, skin, and both ovaries. She showed normal sexual maturation and at age 31 years delivered a normal male infant. The present report describes a chromatin negative patient who exhibited spontaneous breast development at age 12 years. This prompted a histologic and chromosomal investigation, the results of which are discussed below.