Question

(Q001) Glucose-6-phosphate dehydrogenase deficiency (G6PD deficiency) is an inherited disorder where either the body has less of the G6PD enzyme than normal or the available G6PD is not functioning correctly. This deficiency affects red blood cell function and may result in anemia (the destruction of red blood cells) when people with the condition have infections, are taking certain medications, or eat certain foods. People with G6PD deficiency may have some protection from malaria because their abnormal red blood cells interfere with the reproduction of the malaria parasite in their bodies.

Consider the prevalence of G6PD deficiency estimated by the World Health Organization (WHO) as shown in the map on p. 247 of your lab manual. Compare the distribution of G6PD deficiency with the distributions of the sickle-cell trait and malaria shown in Figure 8.9 on p. 238 of your lab manual. What similarities between these distributions do you notice? What differences do you notice?

(Q002) Why might these similarities and differences exist? Be sure to consider the evolutionary context (including the natural environment, cultural practices, and interbreeding).

Answer 1

The g6pd deficiency has uneven spread over the world just like sickle cell anemia, they diseases are significantly found in regions of the world where malaria is endemic. The wide spread over African countries, middle east and few south acian countries suggest their differential spread over world. Both of the diseases give resistance to malaria and the carrier population are at benificial end. This might be the only region for the natural selection of the genetic disorders over evolutionary time scale. The g6pd deffecincy causes susceptibility and sensitivity to serving foods drugs and oxidising factors. Malarial drugs also sensitise the people. While sickle cell anemia causes sensitivity towards oxygen poor environment. In both of the disorders malarial parasites could not survive in RBC that giving resistance to malaria.

The temperatures over these regions and the cultural aspects like consanguinity in population are the other factors increase the spread of these diseases. The consanguinous marriage especially between first cousins increases the risk of inheriting these autosomal recessive disorder to offspring.

The sickle cell and anemia majorly spread in north african countries and g6pd defeciency has most wide spread over man from middle east countries. These variation in spread of these diseases may be atributed to their differences in inheritance patterns. The sickle cell disease is evenly spread among both gender's because of its autosomal inheritance. But g6pd deficiency is most common in male than the female due to its x-linked inheritance.