Help on pedigree/colour computation program Homepage  


The program checks whether a pedigree is valid concerning two aspects:

It also enables to compute the possible colours of the kittens from a given mating (between the sire in box 2 and the dam in box 3).

Several parameters may be adapted, by clicking the "options" button appearing below the pedigree : the number of generations (between 2 and 6), the language (French or English), the book of origin which you wish to limit to (LOOF or FIFe only for the time being), and the display format for the breed and colour (French names, English names or EMS codes).

The current version is limited. See the "restrictions" section.

Instructions for Use:

If you're using the program for the first time, you may want to read the simple step-by-step instructions here.

Each of the pedigree's box displays a button with the box number, 3 fields and a button with an arrow or a letter C. The pedigree boxes, according to their contents, the screen size you're using and the number of generations in the pedigree, may appear on one or several lines.

In order to retrieve the data for a cat already registered in the E.R.o'S. database, it is enough to enter his/her E.R.o'S. number (eg 501571 for Tikky de la Chacolaterie), then click the "number" button. The whole pedigree (4 generations max.) known by E.R.o'S. will automatically be retrieved and inserted. In order not to overcrowd the display, the names of the cats are displayed in a short version without their affix.

In order to enter a cat's data when the cat is not registered in the E.R.o'S. database, you must enter his/her phenotype. Several possibilities are offered in the list, however limited to those permitted by the chosen book of origin. For example, red, cream or tortie abys will not be proposed if the book is FIFe, but will appear if the book is LOOF. Each choice must be confirmed by clicking the ">" button. Since the program does not make use of any client script, the page is regenerated at each button click. In order to speed up things, when several cats must be entered manually in the pedigree, choices can be made in several boxes, then confirmed all at once by clicking ">" in any box.


Underlying genetic model:

The genetic model underlying this program is implemented in databases, and is then able to undergo evolution very easily, either to introduce new genes/allelic variations or to revise the existing ones.

Here is the list of loci currently processed, with their allelic series :

Loci holding genes controlling coat colour and markings:

Loci holding genes controlling coat texture:

Loci holding genes controlling other features:

Many more genes are under study to explain the genetic transmission of other characteristics. One example is the wideband gene (Wb), held responsible to control in a dominant manner the widening of agouti banding (in its extreme form as in the chinchilla). I prefer for the time being consider this transmission as not strictly Mendeleian, but resulting from the effect of several loci ("polygenic effect"). Another example is the spotted gene (Sp), supposedly a locus where the dominant allele (Sp) would cause the breaking of the tabby pattern (mackerel or classic) into separate spots. Yet another example is the Dm gene held responsible for the caramel coloured cats, not handled either in my program.


Current version restrictions:

Only abyssinians and somalis are handled in this version of the program. A more complete version with other breeds is under development.

The gender of the cats imported from E.R.o'S. is not checked for the time being. Hence, a male cat imported in a female box will be considered as a female cat without further checking. This will be improved in a future version.

Tortie non-female cats are not handled either. These are extremely rare and often sterile, but may exist as XXY cats, mosaïc cats, or cats affected by Turner's syndrome (X cats). The program is limited to "normal" XY males and "normal" XX females.

Enhancements from previous versions

Since the 8.8.2007 version of the program, the fact that the same individual appears more than once in a pedigree is fully exploited. For instance, if a ruddy/usual cat (B-) is mated with a sorrel cat (bl bl) resulting in a chocolate kitten (b bl), and if elsewhere in the pedigree this same ruddy cat (who is then B b) is mated with a ruddy/usual cat carrying cinnamon (B bl), with resulting kittens being declared sorrel (bl bl), the program will point out the inconsistency. Cats are deemed to be the same based on their name (either inherited from E.R.o'S. or typed in).

The E.R.o'S. database (Electronic Register of Somalis) :

This database, fully accessible on-line at, contains pedigree data for several tens of thousands of abys and somalis throughout the world and the ages. It is a wonderful tool to browse through the pedigrees which many breeders or cat lovers have entered, or go up the generations to meet the breed founders.


Sosa-Stradonitz ancestors numbering:

This method for numbering ancestors in a genealogic tree consists in giving number 1 to the person (resp. cat) whose tree (resp. pedigree) is being displayed, then giving number 2 to his/her father and number 3 to his/her mother, etc.
The rule is that a person (resp. cat) bearing number n will have a father bearing number 2n and a mother bearing number 2n+1.

For example, the grandfather on the mother's side from number 1 bears number 6 (it is the father of number 3).


© Marie-Bernadette Pautet, 2005-2019
Last page update: 8.8.2007