Abstract: The various embodiments herein provide a cell growth inhibitor derived from p16INK4a gene comprising a C-terminal segment of the p16INK4a gene, two ankyrin repeats i.e. ankyrin III and ankyrin IV of the p16INK4a gene, two loops i.e. loop 2 and loop 3 of the p16INK4a gene and residues along with the loop 2 consisting Phe90, Glu88, Gly89, Asp92 and Asp84 residues. The cell growth inhibitor is a truncated form of the p16INK4a gene and encompasses 66-156 amino acids of a full length p16INK4a gene. The cell growth inhibitor has 42% growth inhibition at 24 hrs. The embodiments herein also provide a method of synthesizing the cell growth inhibitor using a polymer chain reaction method.