molecular biology - Does a man contain all the genes needed to make a woman?

This question is brought on by a Sci Fi novel I am thinking about writing. The plot device involves a colonist in charge of building a population on a new planet who loses his supply of embryos and so forth in the landing. With the artificial "wombs" intact, he populates the planet with clones of himself.

If he wanted to introduce enough variation (without making up new genes, only rearranging) in the population to allow them to be able to reproduce naturally without inbreeding problems, would he be able to? In particular, could he make a woman? Alternately, could a woman (without a Y chromosome) do the the inverse?

At the risk of introducing bias into the answers, the plot as it stands assumes he is a male and he CAN'T do any of the above and he is restricted to clones.

Answer

This answer also involves some speculations as the question is about a good theoretical framework for a science fiction.

You can find in this post about how sperm can be used to produce embryonic stem cells. It would still require an oocyte for doing that.

The question now is- Can you produce oocytes from a male?

You may fuse two X bearing haploid spermatids to form a diploid cell with XX. This cell will also have mitochondria and ribosomes — seems like a decent candidate. Gametogenesis has not been shown to happen in-vitro. Moreover a zygote will need a lot more cytoplasmic resources that you can get from a fused spermatid.

Plus there are imprinting issues as already pointed out by Chris.

Conclusion: Next to impossible

For your question "Does a man contain all the genes needed to make a women": yes he has but does not have the biological machinery to do that (exclusive of the womb).

However if you choose to send a female astronaut for this mission then there may be some hope. As Chris said, there are problems with homotypic fusions because of imprinting issues. But with a supply of ova there can be other ways:

• Make clones using SCNT: limitation is that there would be very little variability.



• Erase imprinting marks and fuse two oocytes: This has not been done yet but this is possible. At this moment we have technology (still incipient for therapy grade), for targeted genome editing. The basic principle involves fusing a DNA-endonuclease with a sequence specific DNA Binding Domain (DBD). Examples include Zinc Finger Nuclease, TALENs and Crispr-Cas. This study demonstrates an engineered system that can deaminate RNA in a sequence specific manner. Based on a similar principle it should be possible to link DNA-(cytosine/adenine)- methyltransferase or DNA-(cytosine/adenine)-demethylase to a sequence specific DBD ¹. This system can be used for targeted epigenetic modification. This would have a little more variation than cloning because of meiotic recombination. Limitation is that there won't be any males, this would perhaps become an Amazonian Planet.

Make sure that your space-shuttle has a good biolab facility :P

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¹ Imprinting is generally implemented by DNA methylation which happens mostly on cytosines.