> you can't tell which are heterozygotes from those which are wild type=20
> without breeding the fish for several generations.>>
>
> It only takes one generation really- cross the suspected heterozygote =
> back to the parent and look at the fry as soon as they are free swimming =
> (perhaps even before they hatch), the lack of pigment should be obvious =
> in about 50% . If two suspected heterozygotes are crossed then 25% =
> should lack pigment.=20
That is only true if you know the parent is homozygous for wild type.
What if you don't have the parents or any other non related stocks?
> If we start with one albino and one wild then all normal looking fry =
> will be heterozygotes, none can be anything else than "splits". I =
> believe, in the interests of the hobby the normal -looking fry from any =
> other mating that doesn't produce any=20
> albinos at all should be sacrificed and the breeding pair subjected to =
> back mating to albinos to determine their status.
Agreed. That at least negates the chances of having fish carrying the
hidden recessive allele. Good point.
Peter Unmack