Question

How do mutations effect individual traits?

Answer 1

Mutations can affect the coding of "base pairs" in the chromosome of an individual by various means like:
1) by Deletion
2) by Duplication
3) by Translocation
4) by Inversion

After all that changes, codes deviates from normal information & can affect individual in negative way. In that manner, Mutations affect individual traits.

Hope this helps!