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There is substancial information that may well be good, but is unsourced. Additionally, much information appears to be POV. This should describe what Outcrossing is not how it should best be done be done.--Counsel 20:04, 8 December 2006 (UTC)

If one uses Mendelian formulas, using the standard charts for the crossing of an individual homozygous for the deleterious trait, placed up against an "outcross" that is homozygous, not carrying the deleterious trait, an increase of the number of individuals either expressing or carrying the deleterious trait is an ubiquitous result. For example, With TT representing the lack of the trait, and tt representing the diseased homozygous individual, the Mendelian formulas would be as follows:

ttxTT = 100% Tt, all offspring carrying...

the number of individuals present in the gene pool would then be 1+all offspring produced, or at least 2 individuals would at least have or carry the gene.Therefore there is an increase of at least one with the use of outcrossing.

Furthermore, if the trait is a dominant one, outcrossing does nothing to remove the trait. In fact it increases the number of individuals who are disease ridden.

YYxyy= 100% Yy, all offspring diseased...along with the homozygous

The previous version was demonstrating a POV supporting outcrossing as The only "natural" form of breeding. This was unsupported by any proper form of documentation or supported argumentation. In practice, nature allows for both in breeding and outcrossing through selection either by natural causes, or by assortative breeding. --Kerheals 09:40, 29 December 2006 (UTC)

This makes absolutely no sense. Of course if you breed an animal carrying the gene for a deleterious trait, you would get more animals with the gene. This is a result of breeding the affected animal and not of outcrossing. Inbreeding would give you the same result, with the exception that some individuals might actually express the deleterious trait. --Dodo bird (talk) 10:30, 12 October 2009 (UTC)
Yeah, I think that Kerheals understands the genetics, but is ignoring the fact that the person doing the outcrossing will take steps to prevent the spread of disease; that's the point of outcrossing. I'm removing some of the edits K has made because they are, at best, out of place. Maybe a note explaining the genetics would be appropriate, but the way it is now just makes no sense. — Preceding unsigned comment added by SCooley138 (talkcontribs) 00:52, 27 February 2013 (UTC)


I'm not a native speaker and also no breeder, but interested in genetics, and it occurs to me the article have some insider language that is hard to understand for someone more familiar with classical genetics, and science. Maybe this is unavoidable. Or maybe you could try to see it from an 'external distance' and consider that the average reader would be no expert in this area. --michael — Preceding unsigned comment added by (talk) 01:39, 15 March 2014 (UTC)


"Outcrossing is now the norm of most purposeful animal breeding, contrary to what is commonly believed."

FOUR citations for this sentence, wow - ??

A closer look at these sources is revealing: The first one does not say anything at all about outcrossing or about "what is commonly believed". The second and third have disappeared from the internet. The fourth is a page giving recommendations on how to breed a certain dog breed without having inbreeding happening.

All four sources are puppy or cat breeding sites. None of them is anywhere near what you might call a serious scientific source. None of them supports either of the claims that are made in the sentence above, neither the one about the norm of breeding nor the one about whatever may be "commonly believed".

Please provide some reputable scientific sources for these statements, or remove the sentence altogether. -- (talk) 23:50, 23 December 2017 (UTC)