Naked Science Forum

Life Sciences => Plant Sciences, Zoology & Evolution => Topic started by: AnkitaA on 17/06/2019 10:46:29

Title: Can we vary the genetic material of a species which is almost extinct?
Post by: AnkitaA on 17/06/2019 10:46:29
Paul asks:

"When a species is almost extinct can we intervene to vary the genetic material to avoid the problems of inbreeding?
I am concerned about some of our NZ parrots."


Can you help?
Title: Re: Can we vary the genetic material of a species which is almost extinct?
Post by: evan_au on 17/06/2019 22:22:08
Techniques like CRISPR can modify DNA and produce variations
- But the success rate is very low: with current techniques, perhaps only 1 in 10 treated cells will end up with the "right" change in the "right" location
- That is a pretty poor result when you have a bird which breeds slowly
- And sometimes there is more variation than was intended; it is hard to get a measure of these "off-target" effects.
- And you don't want to damage eggs of an endangered species whose population is being eroded by attacks by (anthropogenic)  rats and cats...
- Even if you could modify the eggs, it might be wise to have them raised by proxy parents...

You need to identify what sorts of variations you need for the population to become "less inbred":
- You could extract DNA sequences from museum specimens, as examples that are "less inbred"
- You could try to identify "bad" gene variants, and try to correct them to a :known good" variant.
- But identifying "bad" genes is hard, even when you have accurate health records on a million people; it is much harder when you have a small number of kakapo & keas, all with very similar genomes, and little in the way of health records.
- If they were suffering from disease, you could look at introducing more variation into the MHC genes, so they are better able to recognize and fight off pathogens
- But when the opponent is cats and rats, you might need to tweak some aggression genes - or reenable some (currently silenced) dinosaur tooth genes....

See: https://en.wikipedia.org/wiki/Major_histocompatibility_complex