Chihuahua Crossing Forum Closed

That is true :)   You would have to know the lineage of the dogs you are breeding - there can be many recessive genes that, if both parents carry them, show up in the litter.
Those letters you're talking about are called the loci or color series.  Within each of those, there are what is called allele (or genes).  So it depends on all the genes put together
There are 2 melanins in dog's coloring - one is called eumalin, which is dark and covers the framework of the pigment.  The base of this melanin is black, but can also appear as brown.  The other melanin is phaeomelanin, which produces the red, tan and mahogeny colors.  Again - these can be broken down to even smaller genes (or color traits).
So, all said and down - you would think if you mated a fawn with a cream and white - you'd get all fawns, cremes, whites or different combinations thereof.  But, this isn't the case :)
Within the B series (brown), you can have varying colors - if you put a Bb dog - (2 brown series) - you would, most times, assume, that the double B would "mask" all the black - but it would depend if you have true brown, fawn, dilute brown (which can sometimes show as creme) or a dilute red which sometimes looks like fawn.   And, fawn is actually a dilute color.  You'd also have to factor in any other markings - masks, sabling, etc.
I am by no means an expert - but have been studying this also.  I know some basics - can't have red with sabling as red masks black coloring.  Blue is a dilute gene.  Can't have chocolate and red or brindling with red.  As I said before, fawn is actually dilute.   A lot of times dilute colored red is mistaken for fawn.
I guess it's essentially like having a baby - don't really know what you're going to get LOL
As far as the 2 you are asking about - you'd really have to know what colors are in their background.  I have a red and white who came from a red and white dad and all white mom; my fawn sabled came from a black and tan dad and creme mom; my chocolate looks just like her daddy - but her mom was chocolate and tan also and my new little girl who's blue/tan with white markings has coloring of her dad and her mom is brown and white.  So even tho blue is a dilute color - the mom must have carried it somewhere in her line as almost the whole litter came out blue.
Hope i helped and didn't confuse you more :)

LOL - gives me one too sometimes studying it :)

My 17 year old is much better at it - she can do all the punnett squares for genetically pre-disposed traits and colors.

Aaahhhh, to have a young brain again and understand things LOL