linkage

hj0517

Full Member
10+ Year Member
Dec 19, 2007
130
0
0
  1. Medical Student
Hey guys - I'm having a little trouble understanding the concept of linkage with respect to genetic polymorphism and I was wondering if anyone could help me out?

I'm using HY CMB 99 and the clinical example it gives with APKD is a little confusing, I get the meiotic crossover bit - just don't understand the way linkage can be used to work out odds of getting X disease.

Thanks!
 

SomeDoc

Full Member
10+ Year Member
Apr 9, 2007
991
96
256
  1. Attending Physician
Hey guys - I'm having a little trouble understanding the concept of linkage with respect to genetic polymorphism and I was wondering if anyone could help me out?

I'm using HY CMB 99 and the clinical example it gives with APKD is a little confusing, I get the meiotic crossover bit - just don't understand the way linkage can be used to work out odds of getting X disease.

Thanks!

The odds of getting X disease (or more specifically, locus linkage) can be estimated based on the relative distance between two loci of interest. The closer the loci are on the same chromosome, the greater the chance of them being found together on a resultant gamete and vice versa, in the process of meiosis. Let's say that if a) both loci are needed to produce the diseased phenotype (assume autosomal dominant alleles for the loci, and an autosomal dominant mode of inheritance), b) and if the distance between these loci are small, you can conclude that there is a 1/2 chance (2/4 gametes) of producing a gamete with a diseased allele (which contains both loci).
 
Last edited:
This thread is more than 12 years old.

Your message may be considered spam for the following reasons:

  1. Your new thread title is very short, and likely is unhelpful.
  2. Your reply is very short and likely does not add anything to the thread.
  3. Your reply is very long and likely does not add anything to the thread.
  4. It is very likely that it does not need any further discussion and thus bumping it serves no purpose.
  5. Your message is mostly quotes or spoilers.
  6. Your reply has occurred very quickly after a previous reply and likely does not add anything to the thread.
  7. This thread is locked.