genetics Q - sweetiful

[ArchivalUser]

ye i agree with medic concept

only AD ,hetero carrier ,chance to inherit gene s 1/2.
in AR ,it is 2/3.
then what is d ans?
please someone explain clearly!

[ArchivalUser]

oohh c'man hahaha okt3, i thought you had pulled that concept from hittin the books. are you sure this is acurate??!! i think it will be hard to delete it from my mind now because it somehow makes some sense believe it or not. see what you have done, you're turning me into a bad doc hahaha

[ArchivalUser]

COMMON it is from washington school of medecine

[ArchivalUser]

Hey medc, Here is the link about the concept, please read the paragraph)

DEGREE OF RELATIONSHIP AND GENES IN COMMON


http://www.uic.edu/classes/bms/bms655/lesson11.html

[ArchivalUser]

it's something like yours hahaha... however it says that it applies to non-mendelian inheritance or multifactorial. so it doesnt apply to CF...... almost convinced me though

[ArchivalUser]

okt3's concept:

The degree of relationship is simply the power to which (1/2) is raised to reach the fraction of genes in common. First degree relatives have (1/2) of their genes in common. Second degree relatives have 1/4, (1/2)2, of their genes in common, etc.


Keep in mind)))

[ArchivalUser]

i still stick to 1/8 in this one.

2nd gen: 1/2 probability of having carrier offsrping
3rd generation: if both are heterozygous have 1/4 probability of having diseased child

1/2 * 1/4 = 1/8

[ArchivalUser]

ok ok. i looked it up in the population genetics chapter of kaplan biochem. afterall okt3's rule also applies for mendelian disorders like CF. it says that first cousins share 1/8 of their genes

[ArchivalUser]

hi everyone i am a bit confused too . but i think it should be 1/8 reason i think that way is .we know for sure mother is not diseased means she is heterozygous we know that for sure right. now there are only two possibilities that husband can either be diseased or heterozygous right. so drawing punnet for both and probability comes out is 1/2 and 1/4 and result is 1/8
correct me where i went wrong
thanks

[ArchivalUser]

since 1st cousin share 1/8 of there genes and prob of cf in a child of two carrier is 1/4 so anwer should be 32.this particular topic i could not understand please explain