I am not a biologist. I am a software developer interested in genetic algorithms therefore i am probably talking to biologists who also have a knowledge of genetic algorithms. I need to "breed" different solutions to a problem while allowing the number of genes in my solution to vary because i don't know in advance how many genes i need. This is why i need to be able to cross solutions with N genes with solutions with M genes and this is a serious problem. If N and M are very different the problem would be even more serious. I want to know what happens in the biological world. I am trying to understand how much difference in genome is "enough" to prevent interbreeding between different organisms. Would it be possible to say that if less than (approximately) X% of the genes of two organisms are different then they can probably mate and have offspring? Thank you


  • $\begingroup$ It is not just genomic differences that prevent interbreeding. The synteny also matters. $\endgroup$ – WYSIWYG Dec 25 '14 at 11:52
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    $\begingroup$ Welcome to Biology SE! I think this question holds potential, but probably it needs some narrowing down or splitting up in multiple questions: e.g. (1) On the other hand, members from different species have genomes different enough to make interbreeding impossible. Is it possible to explore what happens in-between these two cases? and (2) what happens during evolution? is it just geographical separation that allows genomes two diverge up until the point when two species exist instead of one? are quite different questions. $\endgroup$ – AliceD Dec 25 '14 at 12:13
  • $\begingroup$ A first idea would be that inbreeding is only deleterious because of the possibility of creating homozygous recessive genotypes which then cause lethal phenotypes. If there were no deleterious recessive alleles in either parent, it could perfectly be the case that interbreeding would still be possible. $\endgroup$ – March Ho Dec 26 '14 at 11:17
  • $\begingroup$ MarchHo, i personally can't have offspring if i mate with a chimp female but i can have it if a mate with a human female. The genes of these two organisms differ for something like 1-2%, right? But i don't know my genome differs from the average woman genome. I suppose that 1% difference is already too much but... how much is too much? $\endgroup$ – Johannes Wentu Dec 26 '14 at 11:43
  • $\begingroup$ @JohannesWentu It isn't as simple as genomic %-difference. If there is a mismatch in crucial systems, this can be enought for incompatibility, even if the genome difference is miniscule. You also need to consider other barriers for reproduction, such as behavioural and mechanical barriers. $\endgroup$ – fileunderwater Dec 26 '14 at 13:47