Jo FaY wrote...
>I'm not very knowledgeable about mammalian chromosome, but some plants can
>have variable numbers of extra, small chromosome. In the Allium species
>(chives, garlic, etc) these are called B chromosomes or supernumary
>chromosomes.
>Some mammals also have B chromosomes, but I can't remember any names
>as I only studied chives in my project at York.
I think you may be referring to double minute chromosomes in mammalina cells
ex. DHFR cotaining double minute in Chinese Hamster Ovary Cells (CHO)
or the Mouse DOuble minute Gene (mdm2)
Also thy have found stable linear chromosome like fragements and episomal like
chromosomes in mammalian cells..... though in most cases even with the ability to
automonously replicate they are lost from cultured cells in the absence of selection.
G.
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