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Analysis of Chromosome Segregation, Histone Acetylation, and Spindle Morphology in Horse Oocytes
Published on: May 11, 2017
SRY negative 64,XX intersex phenotype in an American saddlebred horse
D Bannasch1, C Rinaldo, L Millon
1Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, CA 95616, USA. dlbannasch@ucdavis.edu
Abstract:
A female American saddlebred horse was presented for surgical correction of a possible pseudohermaphrodite condition. The horse had abnormal external genitalia and exhibited stallion-like behaviour. No evidence of uterine or ovarian tissue was identified on laparoscopic examination, but hypoplastic testicular-like tissue was removed, although this was found to contain no spermatogonia upon histopathological examination. A karyotype was performed and showed the normal chromosomal complement for a female horse (64,XX). Polymerase chain reaction to detect the SRY gene was negative in peripheral blood as well as the testicular-like tissue. This case represents the first report of an SRY negative XX-male sex reversal intersex phenotype, which is a potentially inherited condition, in an American saddlebred horse.
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