Although as a breeder, we are interested and concerned about all aspects of feline genetics, we pay particular attention to a mere handful of genes.  Most of these deal primarily with color or pattern, but a couple deal specifically with illnesses and diseases that are known to be passed on genetically.

Definitions:

Allele	wikipedia defines this as "...is one member of a pair or series of different forms of a gene..."
Chromosome	wikipedia defines this as "...a singular piece of DNA, which contains many genes..."
DNA
Locus	wikipedia defines this as "...a fixed position in a chromosome, such as a gene or biomarker..."

So what does this all mean?

It means that like all living beings, cats are made up of fundamental building blocks called chromosomes, which collectively make up the DNA of a living being.  Each Chromosome is the designated 'home' for a variety of different genes.  The location of each gene is known as the "locus", wherein a single gene pair, can have one or more attributes.  For a non-technical explanation of genetics, check out wikipedia's "Introduction to Genetics".

Notation Conventions:

In order to clearly denote the difference between dominant and recessive alleles, geneticists have denoted dominant genes in capital letters, where as recessive genes are denoted in lower case letters

 

Dominant vs Recessive:

If a particular cat contains one dominant allele and one recessive allele, the dominant alleles will be displayed physically/visually in the cat.  Although the recessive allele is physically displayed, it can still be passed on to its offspring.  In fact it's offspring may receive the dominant allele or the recessive allele

If the same cat contains two recessive alleles for a given gene, the cat will display that recessive trait, and pass that trait onto all of its offspring.

It is important to note that just because a cat passes on a specific allele, does not guarantee that the allele will be displayed, it is imperative that BOTH parents alleles be considered to determine what physical trait will displaye.

 

Loci of interest to Archadtz

Agouti	Persian Himalayan A cat with one dominant A allele will display the "agouti" trait. Tabby Lynx-Point a if not overridden by a more dominant allele, will not display the "agouti" trait     Archadtz currently does not have any cats that carry the A allele, and therefore cannot produce lynx-point/tabby marked cats.
Chocolate	Persian Himalayan B a cat with one dominant B allele will display the "black" trait. Black Seal b when not overridden by a more dominant allele, will display the "chocolate" trait  Chocolate Chocolate bl when not overridden by a more dominant allele, will display the "cinnamon" trait  N/A N/A
Albino	Persian Himalayan C a cat with one dominant C allele will display the "solid-color" trait.   CPC cb when not overridden by a more dominant allele, will display the "burmese" trait  N/A N/A cs when not overridden by a more dominant allele, will display the "color-point" trait  N/A   ca when not overridden by a more dominant allele, will display the "blue-eyed albino" trait N/A N/A c when not overridden by a more dominant allele, will display the "red-eyed albino" trait N/'A N/A
Dilution	Persian Himalayan D a cat with one dominant Dallele will display the "undiluted"" trait.     d when not overridden by a more dominant allele, will display the "dilute" trait  dilute dilute Note" this gene is what is called a "modifier" gene, and it interacts with the B and O genes.
Inhibitor	Persian Himalayan D a cat with one dominant Dallele will display the "solid-color" trait.   CPC d when not overridden by a more dominant allele, will display the "burmese" trait  N/A N/A cs when not overridden by a more dominant allele, will display the "color-point" trait  N/A   ca when not overridden by a more dominant allele, will display the "blue-eyed albino" trait N/A N/A c when not overridden by a more dominant allele, will display the "red-eyed albino" trait N/'A N/A
Red	Persian Himalayan O a cat with one dominant O allele will display the "solid-color" trait. Red Flame o when not overridden by a more dominant allele, will display the "burmese" trait  Cream Cream Note:  Red is a gender-linked gene meaning that it is only carried on the X chromosome.  A female has two X chromosomes whereas a male carries only one X chromosome.  As a result, this particular gene has a third state, present only for females which have one Dominant O allele and one Recessive o allele     Persian Himalayan Oo only a female cat can carry one of each allele, and she does, displays the "tortoishell" trait. Tortie Tortie
White Spotting	Persian Himalayan S a cat with one dominant S allele will display the " white spotting" trait" bi-color N/A s when not overridden by a more dominant allele, will display the "non-white spotting" trait    N/A Note:  The white spotting gene is one of a handful of genes that when two dominant alleles are present, will result in a more aggressive display of that trait.     Persian Himalayan Ss when one of each allele is present, the cat will show the white-spotting trait over roughly 50% of the body Bi-color N/A SS when two dominant alleles are present, the cat will show more significantly more white, although it will still show some color Van N/A
Dominant White	Persian Himalayan W a cat with one dominant W allele will display the "dominant white" trait. White N/A w when not overridden by a more dominant allele, will display the "self-color" trait    N/A
PKD	Persian Himalayan PKD a cat with one dominant PKD allele will carry the PKD disease. PKD PKD pkd when not overridden by a more dominant allele, will not carry the pkd disease  non-PKD non-PKD