Guys random question but do you guys think I could build a good physique I am only 13 and have barely touches a weight in my life are my genetics good? Also I am flexing in this picture

I think you can! you are young (well the same age as me but still young). keep working and you can.

small, big, or no change could occur in the phenotype. it could cause something as simple as a cats ears to curl backwards or something as frighting as death. it could also occur in the protien-coding area and have an effect on that but no effect on the amino acids. what has to occur is a changing in the hox gene or the control gene.