Nevertheless, cellular aneuploidy is a known feature of over 5,000 sorts of tumour.Adding or subtracting whole chromosomes is a much more plausible way to get drastic alterations in cell behaviour than the mutation of individual bases, Dr Duesberg argues.
By changing the activity of thousands of proteins instead of just one or two gene products, aneuploidy can overwhelm a cell's ability to control its division.
The aneuploidy hypothesis, however, appears a worthy successor.In the case of HIV and AIDS, all subsequent research has shown that Dr Duesberg was wrong.
And the ubiquity of aneuploidy in cancers does need explaining.
These puzzles, he asserts, can be explained by the epigenetic phenomenon of aneuploidy, in which a cell possesses the wrong number of chromosomes.During the process of cell division, copies of chromosomes are lined up and distributed between the daughter cells by a scaffold of proteins known as the spindle.
This condition is called aneuploidy.
Two types of changes in chromosome numbers can be distinguished: a change in the number of whole chromosome sets (polyploidy) and a change in chromosomes within a set (aneuploidy).
The most common form of aneuploidy in humans results in Down syndrome, a suite of specific disorders in individuals possessing an extra chromosome 21 (trisomy 21).
Both aneuploidy (abnormal chromosome number) and chromosomal translocation (part of one chromosome is transferred to another) can be detected by methods such as FISH and CGH.
Other forms of aneuploidy in humans result from abnormal numbers of sex chromosomes.
But morphology does not tell all, and many embryos that look great under the microscope have undetected chromosomal abnormalities like missing or extra chromosomes, called aneuploidy.
