Over the past 160 years there have been many relevant breakthroughs and discoveries allowing the features that underlie both common and rare genetic conditions to be understood. The father of modern genetics, Gregor Mendel, provided an early recognition of human genetic variability using basic modes of inheritance after studying Pisum sativum, the common pea plant, in 1865 [1]. In 1953, James Watson and Francis Crick went on to describe the double helix structure of DNA [2]. This was then followed by the discovery of sequence reactions by Sanger and Coulson [3]. and the polymerase chain reaction technique by Mullis et al [4], which in turn helped make genome sequencing possible. The Human Genome Project was then completed on 21 October 2004, supplying the nucleotide sequence of all chromosomes [5].