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Lesson I

1… Genetics is the branch of biology that studies heredity. There is sooooo much to this subject. We are not even going to begin to scratch the surface, just focus on how chromosomes are related to genetic disorders.

2... There is over 3 feet of DNA in just ONE of your cells!

3... DNA (Deoxyribonucleic acid)……DNA is our genetic “Blue Print”

4... April 25th is DNA Day and……Ivey’s Birthday! Next April 25, we will celebrate Ivey’s birth and the day that Watson and Crick discovered the structure of DNA

5... Genes: No, I didn’t misspell it…(Jeans) They are made of DNA. Our genes are inherited from our parents,one from your mom one from your dad. In essence,they control our heredity.

6... Every human has somewhere between 20,000 - 25,000 genes that determine traits and dictate growth and development.

7... Chromosomes carry our genes and are found in the nucleus of our cells.

8... Humans have 23 pairs of chromosomes .

9... Scientist can diagnose genetic disorders by looking at chromosomes.

10... Human Genome Project
Project that began in 1990 and ended in 2003, structured to identify a complete DNA sequence of the human genome. (maps genes or what scientists call ‘gene mapping‘) Analysis of the data received from this project will take many years. Results may help to cure or predict diseases.

11.. Genetic mutations happen when there is a mistake in the transmission or replication of genetic information. Genetic mutations can be inherited from one parent, both parents or they may be random occurrences. Mutations can be as simple as involving one gene and so extensive that they involve an entire chromosome. Mutations affect a genes’ function.

12... Classic chromosome mutations:
Translocation: Part of chromosome breaks-off and reattaches to another chromosome
Inversion: Part of a chromosomes information is reverse of it’s usual direction.
Duplication: A segment of a chromosome is repeated.
Nondisjuction: A whole chromosome is duplicated or it can be completely deleted.
(Example: Downs Syndrome. Result in having an extra 21st chromosome.)
Deletion: Part of a chromosome is completely lost. Deleted.

13..Ivey has part of her 21st chromosome deleted.

Homework: Just look at the pictures!!
http://www.accessexcellence.org/RC/VL/GG/human.html
http://learn.genetics.utah.edu/units/disorders/karyotype/whatarechrom.cfm
http://www.pharmgkb.org/search/browse/chromosomes.jsp
This one is important to Ivey:
http://www.pharmgkb.org/do/serve?objCls=Chromosome&objId=PA502

Comments

Sarah said…
I'm constantly amazed that such a teeny, tiny piece of our bodies has such amazing force! We don't know where in Addison's DNA things are mixed up, but it's amazing that something so small can have such drastic results. Funny how we can lose an entire organ or limb and still function just as normal, but a missing "q" arm of a certain chromosome can change almost everything about us. Thanks for the lesson--I've been using chromosomes and genes interchangeably and didn't even realize there was a difference. (Guess that's why I studied literature, not science!!)

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