<p> This dissertation focuses on the use of whole genome sequencing (WGS) for the identification of disease causing variants in canine genomes. A brief review on the historical milestones of genetics, the creation and popularization of the fast throughput DNA sequencing technologies and their advantages and potential problems and biases, the importance of the study of canine genetics and the current state of the canine genome assembly is presented. Our lab sequenced ~100 dogs in the attempt to discover disease-causing variants. So far 20 such variants have been identified. This dissertation contains detailed accounts of the discovery variants likely to be responsible for four canine diseases. Those diseases are: Paroxysmal dyskinesia in Soft Coated Wheaten Terriers that is associated to the missense mutation <i>PIGN:c</i>.398C>T; two different forms of neuronal ceroid lipofuscinosis, one in Australian Cattle dogs caused by CLN5:c.619C>T, and one in the Cane Corso caused by the splice site mutation <i>PPT1c.124+1G>A</i>; and a Shiba Inu GM2 gangliosidosis caused by <i>HEXB.c:948_950delCCT</i>. Furthermore, examples of not so successful attempts, possible reasons for failures and suggestions to successfully conclude other ongoing investigations.</p><p>