Copy of the Biology Exam

[Yacoubb]

for genetic screen question, could you say that the individual was a carrier of the gene for the disease but was heterogeneous so did not phenotypically express the trait (the disease)

They may accept this. I think the main answer they were looking for was that although the genetic information to synthesise the autoantibodies was present in the genetic material of the teenager (hence the positive test), the onsets of the autoimmune disease were not till a later period of her life, and so autoantibodies had not yet been produced (hence, negative test for autoantibodies).