00:01
In order to answer this question, let's talk about in shape and she says, you're analyzing the following human pedigree, assume that in the middle mark with an asterisk that not can be any alien associated with the affected phenotype and that no other mutation is potentially of use.
00:17
Youth are for the ali associated with the dominant phenotype and the recessive are for the ideal associated with the acericcissive phenotype.
00:24
So first, this is an autosomal recessive, okay? or i'm sorry, at least this is a recessive.
00:31
Disorder.
00:32
We don't know if it is autosomal or exclaim.
00:35
So let's solve this.
00:38
First, we have to look at here.
00:40
This generation is very important.
00:42
Why? well, because let's suppose first that this is an autosomal recessive disorder.
00:46
If it is an autosomal recessive, then this is the dominant allele and this is the excessive allele.
00:51
So affected people are going to be homozybal recessive like this.
00:56
And remember, that each person in her is one alien from each parent.
01:01
So in this case, this recessive are, came from this parent, and this recessive all came from this parent here.
01:09
So it means that both are going to have at least one with a little.
01:14
This number three can be a calmer, okay, because she has an affected parent, so she can be heterocygos.
01:22
And in this case, this man is unaffected, so it means he is also, a target like this, heterozygos, okay? because he cannot be like this, because in this case, it would be a black square.
01:34
And this is not a case.
01:35
So the only possibility left is being heterocylus.
01:39
But according to this, it says that the individual marked with an asterisk does not carry any allele associated with the affected phenotype.
01:46
So it means that this person does not have the greciapalin, so this person cannot be heterozygalygo.
01:53
Okay, so this does not fit for overdose.
01:55
It means that this pedigree is not for an autosomal recessive but for an ex -linked recessive disorder.
02:04
In this case, this is going to be a normal allele.
02:07
And this is going to be a mutant allele...