00:01
In order to answer this question, let's talk about inheritance.
00:03
This question says, in humans, oculocutaneous albinism is a collection of autosomal recessive disorders characterized by an absence of the pigment melanin in skin, hair, and eyes.
00:13
That is, normal pigmentation is dominant over albino characteristics.
00:16
For this question, assume that the phenotype is determined by a single gene with two alleles.
00:20
If two people have normal pigmentation, so according to this, the homozygous dominant and the heterozygous, where this is a normal allele and this is an albino allele, these genotypes are going to account for normal pigmentation, while the homozygous is going to account for albinism.
00:40
Now, it says, if two people have normal pigmentation, it means they are like this, because you don't know if they are homozygous dominant or heterozygous, because both of them are going to account for normal pigmentation.
00:49
And it says, what possible offspring or what possible phenotypes may be observed in their offspring? well, it actually depends on the genotypes or on their genotypes, okay? so, for example, if they are homozygous dominant and homozygous dominant, then all of their offspring are going to be homozygous dominant, it means normal pigmentation.
01:09
But if one of them is heterozygous and the second one is homozygous dominant, then you're going to have this panel square, where you're going to get that some offspring are going to be homozygous dominant, it means absolutely normal, and some of the offspring are going to be also normal...