What were the genotypes for Lorenzo's aunts and grandparents?

Question

I watched the movie, but I don't remember what it said about this, and I don't have the time to watch the movie.

Answer 1

I'm guessing that your teacher is using Cathy Ross's guide to the film, and you're asking about question 2: ALD is a recessive s*x-linked or X-linked disease. If this is a partial family tree for the Odone's, what are the probable genotypes of the family members listed:

XA = normal neurons and xa = ALD

Aunt #1 . . . . X--X--

Aunt #2 . . . . X--X--

Aunt Dee . . . X--X--

Michaela . . . X--X--

Augusto . . . . X--Y

Lorenzo . . . . X--Y

Lorenzo has to have had genotype xaY, with the ALD phenotype, because his Y chromosome would not have masked the expression of the ALD allele.  Augusto has genotype XAY, because he has no symptoms of the disease.  Michaela has genotype XAxa--she is a carrier, who passed the disease to her son without realizing that it was a possibility.  The other aunts had at least one XA, because they would have to have genotype xaxa in order to show ALD symptoms.  I remember Michaela telling Dee that they had the same genotype, but I don't see how they could be sure of that unless they were identical twins.