Question

Individuals with a defective autoimmune regulator gene (AIRE) exhibit

a. DiGeorge syndrome
b. autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED)
c. severe combined immunodeficiency (SCID)
d. MHC class I deficiency
e. MHC class II deficiency.

Answer 1

Individuals with a defective AIRE gene have autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED), a condition caused by the immune system attacking its own tissues due to an inability to distinguish self from non-self.

Step-by-step explanation:

Individuals with a defective autoimmune regulator gene (AIRE) exhibit autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED). This genetic condition arises when there is a mutation in the AIRE gene, leading to a breakdown in the immune system's ability to distinguish between self and non-self. This results in the body's immune system attacking its own tissues, causing multiple autoimmune diseases to manifest.

It is different from conditions such as DiGeorge syndrome, which involves a deletion on chromosome 22, severe combined immunodeficiency (SCID), known as "bubble boy disease", which is often caused by a mutation that affects B cell and T cell production, MHC class I deficiency, or MHC class II deficiency, both of which are related to defects in antigen presentation.