Date: December 2004
I read your explanation of conjoined/identical twins.
When I had my 'identical' twins 20 years ago, there was speculation in
the medical field that there is another state of twinsome they were
referring to as "identical-fraternal", whereby one egg splits but is
fertilized AFTER the split by two sperm. The result is 'identicals' that
are not so identical. Can you elaborate on this?
In order for the egg to split it must first be fertilized by a sperm. Each
resulting cell receives a complete set of chromosomes, half maternal and
half paternal, so there won't be anymore sperm entering these cells even if
they completely separate from each other to produce identical twins.
Ron Baker, Ph.D.
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