Question

Which of the following techniques serve the purpose of early diagnosis?
(ii) R-DNA technology
(ii) PCR
(iii) ELISA
(iv) Convential method of diagnosis(serum, urine analysis, etc.)

• A. (i), (ii) and (iii)
• B. Only (iv)
• C. Only (iii)
• D. All of these

Answer 1

The correct option is A (i), (ii) and (iii)

• R-DNA technology: Recombinant DNA technology, joining together of DNA molecules from two different species that are inserted into a host organism to produce new genetic combinations. It can provide precise diagnostic information about genetic diseases.
  
• PCR (Polymerase Chain Reaction) involves amplification of the nucleic acid in the pathogen allowing us to detect the pathogen at very low concentration. PCR used to detect HIV in suspected AIDS patients and to detect gene mutations in suspected cancer patients.
  
• Using the conventional method of diagnosis(serum, urine analysis, etc.) early detection of disease is not possible as the markers for most diseases appear late.
• Enzyme-Linked Immunosorbent Assay (ELISA): The basic principle of ELISA is antigen-antibody reactions. ELISA can diagnose infections by detecting the presence of antigens (proteins of the pathogen) in the patient serum or by detecting the antibodies produced against the pathogen.
• So, the correct option is '(i), (ii) and (iii)' .