how can you identify the genotypes?

[michellemaria]

Hey i was just wondering how can you identiry the genotypes of a family member if you know their phenotype?
Thanks

[MrMistery]

It depends on the trait. Generally, you can't

[zami'87.]

Use family tree and must know how the trait is inherited(recessive,dominant, also is it X-linked or on autosome or on mitochondrial DNA).
Anyway draw family tree and even then it’s just a guess-high possibility.
But IF molecular basis is known then u can use some techiniques for DNA analysis like RFLP(restriction fragment length polymorphism). So normal individual has specific pattern of bands and heterozyggous has mixed normal pattern and mutant patern
And heh in Drosophila test cross is used(breeding with recessive parent).

Zami’87.

[baikuza]

hei.. how about genetic test?
already try this?

[victor]

Just do a testcross and backcross.....
Actually, you can do what Mithril suggest...um by the way Baikuza, do you know how to do a genetic test?

[Terry K.]

I think just a basic family genetic history could narrow it down, and when you have kids, you will know for sure, for the most part, unless you have a dominant and recessive gene for a trait, and you only have kids with your dominant, then basically, your up the creek w/o a paddle

[baikuza]

hei.. are human can do testcross???
i think it is to.. HARD to DO...
i can not imagine it....

[mith]

it would be much easier and more conclusive to test the DNA, besides I don't think test crosses for humans are ethical

[canalon]

it would be much easier and more conclusive to test the DNA, besides I don't think test crosses for humans are ethical

To say anythhing about practical (where would you find pure lines, and think generation time...)

Yet DNA testing is not alway easy because before testing you should know *what* you want to test for...