Question

If the total number of different V gene pairs is 1.9x10⁶ and junctional diversity accounts for another 3x10⁷ additional combinations, what is the total diversity of the immunoglobulin gene?

a) 1.9x10⁶
b) 3x10⁷
c) 4.9x10¹³
d) 5.9x10¹³

Answer 1

The total diversity of the immunoglobulin gene is calculated by multiplying the different V gene pairs with the additional combinations from junctional diversity, leading to a total of 5.7x10¹³, which suggests a close approximation to option (d) 5.9x10¹³.

Step-by-step explanation:

The question is asking for the total diversity of the immunoglobulin gene, considering both the number of different V gene pairs and the additional combinations provided by junctional diversity. The total number of different V gene pairs is given as 1.9x10⁶, and junctional diversity accounts for another 3x10⁷ additional combinations. To find the total diversity, we add these two numbers together.

1.9x10⁶ V gene pairs
+ 3x10⁷ junctional diversity
-------------------------
3.19x10⁷ total diversity

Since 3.19x10⁷ is not one of the multiple-choice options, we should look for an error in calculation or interpretation. To calculate the total diversity correctly, we should multiply the number of different V gene pairs by the additional combinations provided by junctional diversity:

1.9x10⁶ x 3x10⁷ = 5.7x10¹³

The closest answer to our calculation is 5.9x10¹³ (option d), which might suggest a minor miscalculation or a typo in the question or answer options.