What do I know about somatic and germ line mutations?

1. The most important difference between germ line and somatic mutations is that germ line mutations are inherited while somatic mutations occur during life and are not inherited.

2.  Germ line mutations occur during the process of cell division known as meiosis. The cells produced in this process are the ones that will become either an egg or a sperm.

3. Somatic mutations occur while a cell is undergoing mitosis. The cells produced in this process will form part of organ tissue. Somatic mutations also occur after conception and during life.
 

Mitosis                Meiosis

  

4.  Germline mutations are associated with genetic diseases.  Different types of mutations that occur in the chromosomes can have effects on the phenotype or can cause cancer. Some examples are: Down Syndrome, Cri du chat syondrome (cry of cat), Turner Syndrome and breast cancer.

5.  Somatic mutations can have no effect on the phenotype, usually causes changes in the genotype. Some of these changes can go unnoticed or silent. If the the mutation is cancerous then the body will keep producing these cells until the person dies. Somatic mutations can affect damages in the bladder, liver and kidney function.

http://www.nature.com/scitable/topicpage/genetic-mutation-441