Re: Platypus genome

[Dann Pigdon <dannj@alphalink.com.au>]

Dan Chure writes: 

> Is anything known about the sex determination pattern in echidnas? 

Evidently:
http://genomebiology.com/2007/8/11/R243 

Males echidnas have one less chromosome (63, to the females' 64). They have 
9 sex-determining chromosomes (4 Y, 5 X), while the females have 10 (all X). 
They've lost a Y chromosome somewhere along the way (much like humans appear 
to be losing theirs). 

The ten sex-determining chromosomes in the echidna however don't correspond 
directly to the ten in the platypus. 


> Dann Pigdon wrote:
> > Steve Walsh writes:
> > > The genome of everyones favourite semi-aquatic monotreme is complete:
> > > http://mednews.wustl.edu/news/page/normal/11692.html
> > > http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=9258
> > > It would have been here earlier but the "sequencing and assembling the 
> > > platypus genome proved far more daunting than sequencing any other 
> > > mammalian genome to date".
> >
> > The sex-determinging genes alone are the most complex found so far in a 
> > mammal (or most other animals for that matter):
> > http://www.newscientist.com/article/dn6568-platypus-sex-is-xxxxxrated.htm 
> > l  
> >
> > XXXXXXXXXX makes a female platypus, XYXYXYXYXY makes a male (with no less 
> > than ten chromosomes involved).


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Dann Pigdon
GIS / Archaeologist              http://geo_cities.com/dannsdinosaurs
Melbourne, Australia             http://heretichides.soffiles.com
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