[lbo-talk] Y: Ain't as Good as X

[Yoshie Furuhashi]

"The original Y chromosome contained around 1,500 genes, but during  
the ensuing 300 million years all but about 50 were inactivated or  
lost. Overall, this gives an inactivation rate of five genes per  
million years. The presence of many genes that have lost their  
function (pseudogenes) on the Y chromosome indicates that this  
process of attrition is continuing, so that even these key genes will  
be lost. At the present rate of decay, the Y chromosome will self- 
destruct in around 10 million years" (R. John Aitken and Jennifer A.  
Marshall Graves, "Human Spermatozoa: The Future of Sex," Nature 415  
28 February 2002).

Subsequent research, to the relief of male scientists in particular  
and the weaker sex in general, has demonstrated that Y still  
possesses 78 genes and that it may have stabilized itself through  
gene conversion, i.e., "the non-reciprocal transfer of sequence  
information from one DNA duplex to another," the type of  
recombination which "has been studied most extensively in  
fungi" (Helen Skaletsky, David C. Page, et al., "The Male-specific  
Region of the Human Y Chromosome Is a Mosaic of Discrete Sequence  
Classes," Nature, 423, 19 June 2003).

Rumors of the demises of Y may have been exaggerated, but Y still  
ain't as good as X.  :->

Yoshie Furuhashi
<http://montages.blogspot.com>
<http://monthlyreview.org>
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