All language subtitles for 87031x_PR_Human_Mendel_Genetics_05_Steps_Linkage_v1-en

PETER REDDIEN: What are our steps?

So we have a pedigree and the first thing we want to do

is try to determine the mode of inheritance for our trait.

Autosomal recessive, autosomal dominant, sex-linked,

and so on.

We talked about that previously.

Next, we want to ascribe genotypes

to the individuals in the pedigree.

We will do that for our disease gene

alleles based on the phenotype and what we can infer.

And for the SSRs, we'll do molecular tests

as we talked about last time to identify

the genotype for the SSRs.

Then we want to look at the pedigree

and identify what are called informative meioses.

And I'll get into that in the second part

of the lecture, what those are.

Then we want to categorize the genotypes of any gametes we

can infer that were generated in the pedigree

as being recombinant or non-recombinant.

So we want to identify any recombinant or non-recombinant

gametes that were generated that produced the individuals

in the pedigree.

And then with that information, we

will then calculate a LOD score.

I defined this as a statistical test

we'll be using at the end of last lecture

that will allow us to get some information about linkage

between our polymorphisms and our disease-carrying gene.

So those are our steps.

All right, so to be able to do this,

we just need to think about--

we've talked about this.

We need to think about how you identify informative meioses

and identify recombinant and non-recombinant gametes.

And then with that information, how do we actually

calculate the LOD score?