Cancer's Random Assault

Cancer's Random Assault

Many people are aware that cancer arises from within, and that random genetic mutations are an underlying cause in the formation of cancerous tumors. However, recently conducted research shows that random mutations may account for two-thirds of the risk of getting many types of cancer, leaving the usual suspects — heredity and environmental factors — to account for only one-third. 

The central focal point of the research were stem cells. In any tissue, the more stem cells present, and the more divisions that occur, the greater the likelihood there is for a mutation to occur. For instance, the cancer risk in the large intestine is 24 times higher than that of the small intestine, and this is based solely on the fact that the stem cells of the large intestine divide 73 times a year, compared to 24 in the small intestine. 

With this information, many doctors believe it a good idea to switch focus from preventative measures, and towards developing better cancer testing, which would allow for earlier detection.  Of course, there are cases such as skin and lung cancer which are influenced very largely by the environmental factors of sun damage and smoking. There are also those cancers that do not correlate with stem cell division, such as thyroid cancer, which is impacted more by heredity. 

I found this to be an interesting perspective on cancer, especially since the researchers believed this "bad luck" to actually be good news for many cancer patients, leaving them with the fact that their lifestyle may not have had as large of an impact on cancer development as they once thought. It lets us know that there are certain things that are out of our control, and all we can do is try to lead a fun and healthy life, without worrying too much.  

Main article: Cancer's Random Assault
Secondary Article: Science Magazine

Genetics May Explain Why Autism Is More Common in Boys

Many years of research has shown that males are at a greater risk for neurodevlopental disorders like autism spectrum disorder (ADS) than females. Also, studies have shown that boys on average are five times more likely to have autism than girls. A recently published article by Carl Engelking clarifies why genetics can explain why this is so. According to geneticists in the U.S and in Switzerland, it has something to do with “female protective model.” This means that females have a higher tolerance of harmful genetic mutations causing them to require a larger number of them to reach a diagnostic threshold of a developmental disorder than males do. So, with identical mutations a male could show symptoms of ASD while a female won’t. However, since the female mutation threshold is higher, when they are diagnosed with ASD it tends to be more severe.

Geneticists analyzed the DNA samples of 16,000 boys and girls who had neurodevelopmental disorders. They found that on average girls with ASD had a 1.3-3 times more harmful genetic alterations than boys. The researchers had suggested that the male brain develops smaller than that of a female so it more subtle genetic changes can trigger ASD. Study author Sebastien Jacuemont of University hospital of Lausanne in Switzerland also studied 800 families in which a family member was affected by ASD. He found that children were more likely to inherit gene mutations from their mothers. The reason for this was because males with autism are less sociable and form less relationships so they are less likely to have children. Whereas females can go unnoticed with the genetic glitches and so in turn are more likely to start a family. 

Although the study did not answer the most profound question, “what causes these disorders,” geneticists are still on the lookout for more insight to answer this question.