Cancer is a disease of cells. It is an abnormal growth of cells which tend to proliferate in an uncontrolled way and, in some cases, to metastasize (spread). Most cancers are considered sporadic. In people who have sporadic cancer, they did not inherit cancer-causing mutations from their parents. Instead, certain cells in their body developed mutations that led to cancer. These mutations can be caused by sun (which can lead to skin cancer), exposure to radiation or some carcinogen, or even random events within the cell. We can detect cancer cells, free “cancer DNA” or “cancer protein” from body fluid(blood, stool and sputum) from cancer patients even when the tumor mass is too small to be visible by radiologic study or endoscopy.

Today, the most accurate parentage testing is molecular genetic analysis, which is a DNA-based test. DNA is the genetic material present in every cell of the human body. Each person’s DNA is unique (except identical twins) and will not change throughout their life time. Every child receives half of their genetic information from his/her biological mother, and half from his/her biological father. Each individual should have half of their genetic characteristics identical to his/her mother. If there are no genetic characteristics shared between the child and the alleged father/mother, the DNA analysis results rule out the alleged father/mother as the biological father/mother of the child. That is why DNA analysis is the most powerful method in identifying paternity.

A sexually transmitted disease (STD) is a disease caused by a pathogen (e.g., virus, bacterium, parasite, fungus) that is spread from person to person primarily through sexual contact. STDs can be painful, irritating, debilitating, and life threatening. More than twenty sexually transmitted diseases have been identified.
STDs occur most commonly in sexually active teenagers and young adults, especially those with multiple sex partners. An estimated 200 to 400 million people worldwide are infected?representing men and women of all economic classes. Most STDs cause relatively harmless disease, producing few or no symptoms. However, some produce persistent asymptomatic or minimally symptomatic disease. Some people carry the disease for days or weeks, while others carry the disease for longer periods, even for life. During this time, an infected individual, or carrier, can spread disease.