understand the general genetics now. Inheritance

[Anna]

I'm trying to understand the general genetic now. How it works? There is a sire and a dam. There will be puppies.

Of course, puppies will inherit genes from both of them, but how it works in general?
Like if I like sire more, which gender puppy will get more from sire - boys or girls?

Which gender pupies get more from father, which - from mother? Is there any rules that works?

Sorry for such silly question, but after reading all these clever articles I'm geting completely confused now.

[gagsd]

All puppies get 50% of their genetic makeup from mom and 50% from dad.
However, many people feel that the dam has a greater influence on the puppies because she raises them and they may pick up habits from her in those early weeks.
Mary

[Anna]

Is there any system, what puppies get more often from sire, and what - from dam? Like temperament from dam, coat from sire and so on...

[Vinnie]

I don't think it's as simple as a 50/50 split or breeding dogs would be a snap. Just like with humans, some kids come out inheriting more from mom and some more from dad. I think it has more to do with whose genes are more dominant and in which areas.

[ellen366]

genetics is not a simple matter; yes, you get 50% from each parent, but dominant and recessive trait combinations determine what the pups will be like in appearance, behavior, temperament and so forth; genetics is a very complicated study..you need to know what the dogs' dna carries and then consider the likely/probable result of the combination of those dogs' dna

[lhczth]

It is 50% from each, but the relationship of dominant to recessive genes will effect how the genes are expressed. Like in the easy case of color where a puppy that inherits the sable gene from say dad will be sable no matter what color mom was because sable is the dominant color. Or in the case of a black puppy it had to have inherited black from both parents because black is recessive.

There are also sex-linked genes. The best known is the gene for Hemophilia A which is found ONLY on the X (female) chromosome. Male dogs carry a Y and an X and the females two X. So, a male, XY, only needs one gene to have Hemophilia A AND can only pass the bad gene on to his daughters. A female would need two sets of chromosome with the bad gene to have the disease, but can pass it on to her daughters and her sons.

When breeding, how the genes match up is totally random for the most part. That is why puppies (or kids) are not identical. An animal that is very prepotent, one that consistently passes on desirable traits, generally will have more homozygous (two of the same) pairs of genes. For example a dog that is homozygous for sable will always produce sables. The other term is heterozygous (different genes).

[Vinnie]

Thanks guys - I knew there was more to it than a 50/50 split.

[pupresq]

Their genotype (what they are genetically) is always necessarily a 50/50 split but their phenotype (who they are physically - what they look like etc) is dictated by which alleles (different variants of a certain gene) were dominant and which were recessive - and to make it even more fun, you've got co-dominance and crossing over and...

[Andaka]

Quote: and to make it even more fun, you've got co-dominance and crossing over and...

Plus you have the polygeneic traits (more than one set of genes make up the trait) such as hip dysplasia. Which is why breeding two OFA certified dogs will NOT guarantee you progeny with perfect hips. But it does improve the odds quite a bit.

[DianaM]

Then there's prepotence- does a stud or bitch reliably reproduce itself in its offspring or are the puppies not much like the stud or the bitch? Does the line have a pretty predictable type or is type all over the place? Often, puppies may be better reflections of the grandparents than the parents themselves. Sometimes you'll have a throwback to a few generations down the line, good or bad. In many human families, children may closely mimic the father or the mother or even the grandparents. I look very much like my dad, my voice is nearly identical to my mom's, but my mom tells me my attitude is a little too much like my grandmother's! With my fiance, he's almost a clone of his dad but his brother is extremely similar to his mom. There is not much blending of characteristics that I can discern; little things, but it's funny how the genetics split so obviously with them. It can be the same in animals. In my cichlids, I can tell who's sired by the dominant SOB in the tank because the offspring look like him and are also clearly dominant SOBs as well.

Read about Mendel and Mendelian genetics and you'll have a pretty good start to understanding the basics.