Re: What type of genetic information does a new baby contain

Dear rasheed,
A new-born baby contains the same genetic information that it received 
from the mother (in her egg or ovum) and from the father (in his sperm).  
This means 50% of the baby's genes come from each parent.  This is ALWAYS 
the case, even if a child looks much more like one parent than the other.

The first cell made when the sperm and egg fuse is called the ZYGOTE.  
The genes inside every cell of our bodies are copies of copies of 
copies.....of that original cell.

Just like a photocopier, though, the copying process sometimes makes 
mistakes, which will be passed on to the next gerneration OF CELL.  
Therefore, as we live our lives, every cell in our body becomes more and 
more copies away from that original cell - so more mistakes appear.  
Cells that deivide rapidly (like skin cells) tend to acquire the mistakes 
more quickly, so moles and 'age-spots' and other signs of aging in our 
skin are PARTLY caused by this build-up of errors.  The other main cause 
of them are mutations caused by our ebnvironment - everything from 
radiation and the sun to smoking and our food.

The genes I have written about above are all in the nucleus of the cell 
and are held in the chromosomes.

But that is not the ONLY place that DNA can be found in a cell.  The 
mitochondria also contain DNA - this time in a simple loop, NOT on a 
chromosome.  About 1% of the DNA in a human cell is in the mitochondria.  
Now, when the sperm enters the egg, only the nucleus fuses with the 
ovum; the rest of the sperm is discarded.  So ALL the mitochondria in the 
zygote are from the mother's egg.  Thus we can trace our mitochondrial 
DNA back through our MOTHERS (all the way back to Eve!)

The Y chromosome, on the other hand, can only come from the father's 
sperm, so, similarly, the DNA in that can be traced all the way back to 
Adam!

Confusingly, when scientists have done this, they get different numbers 
of Adams and Eves..........!

I hope this answers the question!