polyploidy/aneuploidy/euploidy

Elizabeth Larkin elarkin at NMT.EDU
Wed Sep 8 11:02:29 EST 1999


After doubling of the sex chromosomes meiotic separation of the gemini
would yield only one type of gamete, even in the heterogametic partner,
giving only one type of offspring e.g.
XXXX diploid females yields XX gametes.
XXYY diploid males yield XY gametes.
producing XXXY offspring (male?, female?) 

These are variations that occur. Klinefelter males are xxy ( in fact any excess in x chromosomes with a y is a klinefelter and male). Happens in both cats and humans, but the males are sterile and in humans generally retarded and show female secondary sex characteristics. 
Super males xyy are thought to be the cause of aggressive tendencies in repeat criminals, 
Any excess (xxx) or lack (xo)  is called a turners syndrome. These also lead to sterility, retardation and other problems, the more copies the more problems. It is thought that these people survive because the extra x's are "turned off" in the form of a barr body.
	



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