Answer: The effect will be either an abnormal protein, a non functional protein or a protein with altered function or functions.
Explanation: Every protein performs at least one specific function. Example is the case of sickle cell disease where a protein called haemoglobin which is responsible for oxygen transport in the body is mutated. In the sickle haemoglobin, valine replaces glutamate at position six of the two beta chains. Haemoglobin is a protein with four subunits made up of two alpha chains and two beta chains. The substitution of glutamate residue withwresults valine results in the haemoglobin having low affinity for oxygen binding and consequently, inefficient supply of oxygen to the cells.