Isochromosome Y in an infertile heifer.
The chromosome makeup of a 3-year-old crossbred heifer was examined in an attempt to explore the cytogenetic causes of her infertility. The heifer proved to be a mosaic carrying predominantly XY cells and with approximately 30% of cells lacking a normal Y. The minor population included cells carrying a dicentric isochromosome Y and a small proportion of XO cells. Histological features of the gonads and reproductive system suggest that the presence of cells resulting from isochromosome formation and the consequent loss of the Y chromosome segment required for testicular induction may have been causally related to the embryonic state of the gonads and malformation of the duct system noted in this heifer.
Pinheiro
L E
LE
Department of Clinics and Surgery, FCAV, UNESP, Sao Paulo, Brazil.
Mikich
A B
AB
Bechara
G H
GH
Almeida
I L
IL
Basrur
P K
PK
D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000235:genetics*; D002869:Chromosome Aberrations; D005260:Female; D007247:Infertility, Female / Q000235:genetics / Q000662:veterinary*; D007621:Karyotyping; D008677:Metaphase; D012733:Sex Differentiation; D014960:X Chromosome; D014998:Y Chromosome