In this task, you are given a sentence. You are expected to recognize the name of gene or protein. Although there might be several correct answers, you need to write one of them.
Q: Twelve patients of leprosy with arthritis and 161 patients without arthritis were studied for immunological parameters like immunoglobulins ( IgG , IgM , IgA ) , C - reactive proteins and rheumatoid factor .
A:
rheumatoid factor