Personal genomics has been a hot topic since the completion of the human genome project. The vision of personal genomics is that when have the data of each person's genome, we are likely to know what disease each person are likely to get in the life time. As a result, personalized treatment and intervention can be implemented to minimize the damage to the patient. There are a few companies were created based on this paradigm such as 23 and me, navigenetics, etc. However, the amount of clinical out come coming out of these companies had been limited. The question is "Is personal genomics really going to be useful?" "Will it eventually become an non-dispensable technology to transform the medicine?"

For the first question, the answer is partially yes. It will be useful on some diseases, but not all. Infectious disease and classical surgery are very unlikely to benefit significantly from personal genomics. The infectious diseases are typically caused by the invasion of bacteria and/or virus. Most of the medicines of combating bacteria are the inhibitors of the enzymes inside the body of the bacteria. Understanding of the variation of the host(human) are very unlikely to help those inhibitors to work better. The classical surgery are also unlikely to benefit from the personal genomics, for example, tooth extraction, the detailed information of tooth growth probably won't help surgery much. Although the genome encodes how the tooth are suppose to grow, the environment will have a impact on how eventually the tooth are going to look like, thus personal genomics cannot replace dental X-ray.

What diseases that personal genomics will likely to be useful? I think complicated genetic diseases are likely to benefit from personal genomics most. Some complicated genetic diseases such as diabetes, rheumatoid arthritis, and cancer. These diseases are the results of faulty metabolic pathway, these pathways comprises multiple components, each of them can be faulty. Diagnostic method at each nucleic acid base pair level are likely to help to pinpoint the faulty parts of the pathway. Fault specific therapeutic strategies are likely to be more effective than a generic treatment.

However, there are still gaps between this vision and the current understanding of those diseases. To accurately identify the faulty part of the pathway, first we need to understand what constitute a healthy pathway, second, we need to understand what variations of the pathway are diseases related. Our knowledge of both questions are limited for most of the genetic diseases. Furthermore, variation specific treatment can be even further down the road after we understand the impact of each type of variation.

We can forsee that personal medicine for genetic diseases is a very tantalizing vision with very long way ahead. In the meanwhile, the technology to discover/store/simulated genetic variations will definitely help realize this vision faster, this is where computer will be extremely useful.