HLTB20H3 Lecture Notes - Lecture 5: Edwards Syndrome, Down Syndrome, Environmental Factor
Document Summary
Lecture 5: examples of human variation simple traits and genetic disease. All disease has come genetic component in its causation. In all of the common disorders (non-rare) the genetic component in etiology is polygenic. Comment [ag2]: this number is always changing normally increasing. Comment [ag4]: genes for enzymes that are not present. So you have a mutation that prevents a certain gene for a enzyme to not be present, and therefore certain proteins are not being made, certain carbohydrates are not being produced, etc. Comment [ag5]: not always the case, sometimes one gene. Can be genetically influenced (each individual has 50-100,000 different genes) Alterations or combinations of these can produce genetic diseases. Approximate prevalence of genetic disease in the general population. 20 50: diseases of simple inheritance or simple mendelian inheritance. Simple mendelian causes: simple dominant, simple recessive, simple co-dominant, sex-linked genes. Because patient cannot convert, they accumulate phenylalanine in their bodies, which is toxic.
