Question

Which disorder is associated with the gene DISC1, and how does the disease gene originate?

a) Alzheimer's disease; the DISC1 gene mutates due to environmental factors.
b) Schizophrenia; the DISC1 gene is inherited through autosomal dominant transmission.
c) Huntington's disease; the DISC1 gene arises from somatic mutations.
d) Bipolar disorder; the DISC1 gene experiences random mutation during cell division.

Answer 1

The gene DISC1 is associated with schizophrenia and is inherited through autosomal dominant transmission, meaning it takes only one copy of this gene to potentially express the disorder.

Step-by-step explanation:

DISC1 is a gene that is associated with schizophrenia and related psychopathologies such as bipolar disorder. The correct answer to the question is b) Schizophrenia; the DISC1 gene is inherited through autosomal dominant transmission. This means that only one copy of the mutated gene needs to be present for the disorder to be expressed. The DISC1 gene does not relate to Alzheimer's disease, Huntington's disease, or occur due to somatic mutations as the other options suggest. Alzheimer's disease, for example, has been linked to mutations in several genes, including the APOE gene, particularly its E4 variant, not DISC1.

Autosomal dominant genetic disorders, such as Huntington's disease, require only a single copy of the mutant allele for an individual to express the disease. This differentiates it from autosomal recessive disorders, where two copies of the mutant allele are necessary for the expression of the disease. Mutations leading to these disorders can arise spontaneously or may be inherited from a parent.