Question

Why do different people experience the same disease differently? Or asked another way, why do pathogens cause different symptoms in different people?

Suggest two or more well-founded reasons for this difference.

Answer 1

Yes, two different individuals differ in experiencing symptoms of the same disease.

This difference is due to many reasons such as :

1. Genetic dissimilarity: No two individuals have the same genetic composition, even two homozygotic twins differ in their genetic composition.

2. Genetic recombination: During meiosis, the genetic recombination process not only leads to the daughter cells differing from the parent cell but also from each other.

3. Epigenetic marks: Even though siblings have relative genetic composition, they differ in their epigenetic marks according to how they are exposed to certain environmental conditions.

4. Along with this, immunity and resistance of certain individuals and their susceptibility are different and so some of them end up having mild symptoms whereas the others having severe symptoms. Immune system works differently for different age too, for eg. you can see in COVID 19.

5. At last but not the least, the range and time of exposure to a certain pathogenic agent can vary.

I hope this answer helps!

Best regards!