The human GM-CSF gene and the mouse GM-CSF gene vary by more than 60% in their DNA sequence. However, when scientists place the human gene into mice, it functions properly. What best explains why this happens?

A. The difference between gene sequences does not change the structure of the proteins.
B. The resulting proteins made by the human gene are similar to the proteins made by the mouse gene.
C. The mouse DNA is a mutated form of the human GM-CSF gene.
D. Mice can make human protein without the use of the human GM-CSF gene.

The human gene when placed into the mice functions properly because the resulting proteins made by the human gene are similar to the proteins made by the mouse gene.

What is the GM-CSF gene?

The Granulocyte-macrophage stimulating factor or GM-CSF are glycoproteins secreted by immune cells. These are secreted by the GM-CSF gene. These factors function as cytokines in the body

This factor causes the activation of macrophages in small numbers and produces a rapid immune response against a pathogen. GM-CSF also influence mature cells like neutrophils to enhance their migration. Therefore GM-CSF plays a great role in the activation of the immune system against a pathogen and promotes its defence mechanisms.

Thus, even if the human GM-CSF and mouse GM-CSF vary by up to 60 per cent in their DNA sequence, human GM-CSF functions properly in nice because their resulting proteins are similar to each other.

Therefore correct option is B.