Human Genetic Disorders 1 How are genetic disorders

Human Genetic Disorders 1. How are genetic disorders inherited in humans? 2. How are genetic disorders traced, diagnosed and treated?

How are genetic disorders inherited? �What is a genetic disorder? An abnormal condition that a person inherits through genes. Some are caused by mutations in the DNA and others are caused by the structure or number of chromosomes. �Cystic fibrosis: body produces abnormally thick mucus in the lungs and intestines making it hard to breath. o You need two mutated alleles to have the disease. o The mutation causes 3 bases to be removed from the DNA �Sickle-Cell Disease: This crescent shaped blood cell can not carry as much oxygen as a normal blood cell

Diseases cont. �Hemophilia: blood clots slowly or not at all. Small bruises and bumps can cause internal bleeding. It is a sex linked disorder so it occurs more in males. �Down Syndrome: Have an extra copy of chromosome 21 in every cell. The error occurs in meiosis (when sex cells form). People have mental retardation and heart defects.

How are Genetic Disorders traced, diagnosed, and treated? �Pedigrees: a “family tree” that tracks genetic traits �Karyotype: a picture of a persons chromosomes

�Genetic Counseling: Genetic counselors help couples understand their chances of having a child with a particular genetic problem. They can also prepare couples that are expecting a child with a genetic problem. �How can people deal with these problems? �Physical therapy, helps remove mucus from the lungs of people with Cystic fibrosis…

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