Hmm… I have been thinking my way through the genetics here...

I would be interested in seeing the article on fish breeding with respect to outcrossing highly inbred lines. In the lab, we regularly outcross mutants derived through mutagenesis to remove background mutations and normalize the genetic background (as much as possible) relative to the wildtype. Of course, we can usually follow the mutation of interest (by PCR, for example) through the outcrossing process, and simply rely on diluting any deleterious alleles through repeated outcrosses. I guess an argument against outcrossing is that it can simply conceal a deleterious recessive mutation by making it heterozygous, in which case it may reappear in subsequent generations. In addition, if the deleterious allele is tightly linked to the desired trait, it may be difficult or impossible to separate the two. If there is no other way to sustain the line (and it is a matter of personal opinion whether it would be worthwhile to do so), then outcrossing may be the only option (and it may not work). Personally, I think the albino Woodhouse’s toads look fabulous and I would love to see them preserved and improved through careful breeding.