A group of researchers performed a genetic survey of two different human populations, one living in a deep tropical forest and the other in a faraway metropolitan city of the same country. Their haemoglobin genes were analyzed and classified as normal or sickle cell anaemic. Five years later, the same group of researchers performed another survey for the occurrence of malaria in these two populations. The reports are tabulated as follows:




Sickle cell anaemia manifests in an individual because of a defective haemoglobin gene. Assuming that the rate of exposure to malarial parasites remains constant both in forest and in the city during the last 100 years, and other compounding factors do not exist, which of the following statement(s) is/are most likely to be correct?

• Correct answer
  A

  The percentage of individuals dying due to anaemia in both forest and city is almost the same.
• Correct answer
  B

  Individuals carrying gene for sickle cell anaemia are better protected against malaria.
• Correct answer
  C

  Malarial infection is independent of the haemoglobin gene.
• D

  Individuals carrying gene for normal haemoglobin are better protected against malaria.

Hence, the correct answer is options: 'A', 'B', 'C'.