What is with albino kribensis genetics?

[alanmin4304]

I have a tank with a few kribs (all albino) and they have spawned a couple of times. When young I was suspicious but now they are bigger it is clear that about 10% are going to be normals. I always thought that the albino gene was about as recessive as it gets. How could this be or do I need better glasses?

[Ktttk]

Interesting you mention this Alan.. because a pair of my albino BNs have produced 100% brown offspring...

They've bred twice now and have thrown 100% browns on both occasions.

Guess I'll grow them up, breed them and see if they carry the recessive albino gene.

[new2discus]

Genetics are difficult at the best of times, the only real way to fully start to comprehend the combining ability and recessive or non recessive genes is to keep acurate records over a long period of time. It is worth noting that 1 parent can and will give completely different results depending on the partner (think racehorses). The square formula is an idealistic view and often doesn't apply in real life.

[Dixon1990]

Did you breed these with the male from me alan?

[ryanjury]

Guess it would be very hard because you wont know the definite parents genetics back say x generations..

[alanmin4304]

I have 3 males with 8 females and one that has bred is from Dixon. I would expect that you could get albino young from 2 normals carrying the albino gene but not normals from albinos.

[new2discus]

Just because the fish looks physically like an albino, doesn't mean it is entirely albino, will still probably be carrying the normal gene, which is dominant over the albino....BUT you would expect SOME albino from an albino x albino, not all normal :-?

[Ktttk]

Just because the fish looks physically like an albino, doesn't mean it is entirely albino, will still probably be carrying the normal gene, which is dominant over the albino....BUT you would expect SOME albino from an albino x albino, not all normal :-?

As I understand it, if the normal gene is dominant (and the albino one recessive), then the phenotype of any fish carrying it will always be normal. A fish that looks albino will therefore not carry the normal gene.

A possibility is that there are two different forms of the albino gene i.e. two separate locations in the chromosomes where albino genes reside. I remember reading about this somewhere.. will have to do a bit more research..

[alanmin4304]

ktttk---well said. i just found it hard to understand how two recessives could throw a dominant (and only about 10%)

[jn]

simple mutation back to the dominant form??

my brother and his wife are brown-eyed - they have 2 brown eyed daughters and hazel eyed son, no she didn't visit the milkman.. when they performed their usual tests during her pregnancy with the son they found some abnormality which caused some concern, they then said everything was fine.. so perhaps the gene error they spotted resulted in the different eye color?

[wilson]

simple mutation back to the dominant form??

this may count for a few but not all of them

[Freakyfish]

I have read a few things about Kribs and apparently the Abino Gene isnt reccessive

Brad

[alanmin4304]

It can't be dominant either. As an aside I understand that the sex is related to water hardness, is this so? I bought 10 babies and they were all females.

[firefish]

I read in my yr 13 bio book today that some albinism is caused by a lack of an enzyme which creates the melanin pigment so maybe the parents don't have the enzyme and the babies somehow managed to produce it...

[wilson]

the babys would need the gene to produce the enzyme