Human Disease Caused by a Gene Mutation

Gene mutations that cause human diseases usually occur randomly but are sometimes caused by environmental factors such as smoking, according to Medline Plus. Autism, cystic fibrosis, Down syndrome, hemophilia and Parkinson's disease are all human diseases caused by a gene mutation, according to the National Human Genome Institute.

Autism

• Approximately one out of 91 children are born with autism, according to the Autism Society of America. According to the Mayo Clinic, there are many different types of gene mutations that can cause autism.

Cystic Fibrosis

• Cystic fibrosis affects approximately 70,000 people worldwide and is caused the deficiency of a protein product caused by a gene mutation, according to the Cystic Fibrosis Foundation. Cystic fibrosis can be life threatening and affects the lungs and the digestive system.

Down Syndrome

• The National Down Syndrome Society says Down syndrome occurs when a person has two or three copies of their 21st chromosome. Down syndrome causes lifelong mental retardation that can vary in severity.

Hemophilia

• Hemophilia is a disorder that effects the formation of blood clots. According to the National Heart Lung & Blood Institute, people with hemophilia bleed longer than others when they cut a scrape or cut.

Parkinson's Disease

• One of the first signs of Parkinson's disease is twitching in a person's limbs. The Parkinson's Disease Foundation explains that Parkinson's disease is caused by a combination of genetic and environmental factors.