Donna Anastasi <[EMAIL PROTECTED]> wrote
>As I understand it...
>
>The spotted (Sp) is a weird gene. No it is not a recessive - if you
>have it, it's visible.
>An spsp pup will have no spots
>A Spsp or spSp will have spots
>A SpSp will be absorbed in the womb and never be born.
Yes. SP is probably best described as a semi-dominant homozygous lethal.
It is semi-dominant because if it were fully dominant Spsp gerbils would
not live, just like SPSP ones. Other species with similar genes strongly
suggest that SPSP would produce a completely white gerbil if it were
able to survive.
>
>Also of interest Sp could show as a small spot, a few spots, or as pied
>(blaze and ring around the neck).
Yes.
>The amount of white cannot be
>controlled in breeding.
This is only partially true. The exact pattern and the precise amount of
white is subject to random and/or environmental factors. However, the
amount of white can be increased, or reduced, by selective breeding over
many generations. This is consistent with other species where the same
process applies. The exact markings will not be inherited, but modifying
genes that will tend to produce more, or less, white, can be passed on.
--
Julian
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* Jackie and Julian *
* [EMAIL PROTECTED] *
* National Gerbil Society *
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