Parkinson’s disease is a degenerative disorder occurs after the huge loss of dopamine producing cells (30%-70%) in the substantia nigra inside the patient’s mid-brain. Dopamine plays a major role in movement, mood, memory and attention. In this research, researchers are working on PD related to the LRRK2-G2019S mutation, which is one of the common genetic causes for PD. It also occurs in North African Arabs and Ashkenazi Jews. They are studying the effect of a natural extract named Theobromine (it can be found in the cacao beans). The effect of Theobromine in slowing down the progression of PD symptoms has not been published, but there is another study related to this mutation that had been published in 2013 They test the hypothesis of possible change in the cell lines of LRRK2-G2019S mutation related to Parkinson’s cases after exposure to Theobromine. To test the hypothesis the researchers are studying (cortex and striatum) cell lines in the lab, the experiment includes: 1. grow the cells in three groups(control-experimental A-experimental B) 2. Silence the experimental group (produce the expression of LRRK2 gene) 3. Affecting the cells in the experimental group B with Theobromine by following drug essay protocol. 4. Study the changes between the cells in the control and experimental groups by looking at the following (growth-size-shape-toxicity) They also looked for the mutation existence in three patients blood samples by following DNA extraction, PCR and gene sequence protocols but the mutation did not exist.