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Dharkwolf · 19-04-2006, 23:40

Lethal genes are actually very hard to spot - and deserve to be explained a little better.

Albinism - already a rare condition - is certainly not a lethal gene - dogs of several breeds are born and can live with this gene. Certainly not terribly well and probably not as long as a normal dog, but they are actually born. (Hypothetically Albinism could be lethal to wolfdogs - as no albino wolfdogs have ever been born. On the other hand, and far more likely, the allele for albinism is simply not present in the CSV genetic pool)

A lethal gene is usually defined as a gene which prevents the foetus from actually being born - you either get still birth or else there is actually no conception at all.

The classical example is that of coat colour in mice - the YY (as opposed to Yy) is actually a lethal combination for that allele - no mice will ever be born which carry a YY gene combination as it is lethal.

Formal Medelean genetics will tell you that you need to look for the various ratios of allelic expressions - if you find a situation where a cross between two heterozygotes results in a 2:1 phenotype ratio - then you've probably found a lethal gene expression (normally you would expect to find either a 3:1 for traditional dominant/recessive alleles or a 1:2:1 expression pattern for codominant genes)

Unfortunately there are very few if any traits which to my knowledge have been identified in CSVs as corresponding to an allele - certainly there are some generic ones (such as coat colour) but the Wolfdog gene pool seems to be remarkably homogeneous at least in what observable traits there are (ie all wolfdogs have agouti type fur etc)

If someone has an idea on traits or lists of traits which can be found in wolfdogs and are known or reasonably suspected to be linked to an allele I would be very interested in learning more about that.

Oh and a word on lethal genes - I am not sure that it is something which breeders need to be worried about or overly concerned over - if you accidentally stumble across a lethal gene expression pattern that pup will never be born and you will probably never know about the fact. However it is certainly a fascinating subject.

19-04-2006, 23:40	#5
Dharkwolf Junior Member Join Date: Nov 2004 Location: Brussels Posts: 201	Lethal genes are actually very hard to spot - and deserve to be explained a little better. Albinism - already a rare condition - is certainly not a lethal gene - dogs of several breeds are born and can live with this gene. Certainly not terribly well and probably not as long as a normal dog, but they are actually born. (Hypothetically Albinism could be lethal to wolfdogs - as no albino wolfdogs have ever been born. On the other hand, and far more likely, the allele for albinism is simply not present in the CSV genetic pool) A lethal gene is usually defined as a gene which prevents the foetus from actually being born - you either get still birth or else there is actually no conception at all. The classical example is that of coat colour in mice - the YY (as opposed to Yy) is actually a lethal combination for that allele - no mice will ever be born which carry a YY gene combination as it is lethal. Formal Medelean genetics will tell you that you need to look for the various ratios of allelic expressions - if you find a situation where a cross between two heterozygotes results in a 2:1 phenotype ratio - then you've probably found a lethal gene expression (normally you would expect to find either a 3:1 for traditional dominant/recessive alleles or a 1:2:1 expression pattern for codominant genes) Unfortunately there are very few if any traits which to my knowledge have been identified in CSVs as corresponding to an allele - certainly there are some generic ones (such as coat colour) but the Wolfdog gene pool seems to be remarkably homogeneous at least in what observable traits there are (ie all wolfdogs have agouti type fur etc) If someone has an idea on traits or lists of traits which can be found in wolfdogs and are known or reasonably suspected to be linked to an allele I would be very interested in learning more about that. Oh and a word on lethal genes - I am not sure that it is something which breeders need to be worried about or overly concerned over - if you accidentally stumble across a lethal gene expression pattern that pup will never be born and you will probably never know about the fact. However it is certainly a fascinating subject.