Gregor Mendel is the father of genetics because he discovered dominant and recessive traits and also that traits are randomly and statistically given from parents to a child. His discoveries established the fundamentals of genetics that are understood in modern science.
Mendel conducted an experiment using peas to prove his theory on the randomness of traits. He disproved the concept that children inherit an equal portion of genes from both parents. He was the founder of the Law of Segregation, which states that traits are passed on based on dominant or recessive alleles. A dominant allele overcomes a recessive allele. Furthermore, his Law of Independent Assortment addresses the random inheritance of traits in which some traits are independent of those of the parents.
Without Mendel's research, which was largely discredited until the 1900s, it would be difficult to understand genetic diseases or engineer different plant species today.