2.1.1

1. MI 2.1.1

2. Family Bulletin #2 – Baby on Board • Read the bulletin • Update your family tree with the information that is presented in it. • 5 minutes – silent. 1 minute – discuss. 2 minutes – silent.

3. Cracking the Code Clips • Clip 2 – Getting the Letters Out • Clip 4 – The Sequencing Race Begins • Clip 6 – Genetic Variation • Clip 11 – The Finish Line

5. Human Genome • The sequence of the human genome is merely a “parts list.” • Now, scientists are working to discover how all of these parts fit together and to figure out the function of each gene. • These studies can help test for specific genetic disorders and provide options to individuals even before they become sick.

6. What is Genetic Testing?

7. Today • You will begin activity 2.1.1 • By the end of the period you will be able to • Argue one side of the ‘Is genetic testing a good idea?’ debate. • By the end of the period you will be able to • List four types of genetic disorders and classify descriptions of disease into one of the classifications.

8. Activity 2.1.1: Chronicles of a Genetic Counselor Introduction • Both of the Smith brothers are faced with difficult questions regarding the health of their future offspring. James and his wife will soon be having a new baby. Aaron and his wife are hoping to become parents. Tests that screen for abnormalities in the genes can provide information about their children before they are conceived or before they are born. They both hope that a genetic counselor can offer advice and help them navigate their reproductive choices. A genetic counselor can help a family understand the risks of having a child with a genetic disorder, the medical facts about an already diagnosed condition, and other information necessary for a person or a couple to make decisions suitable to their cultural, religious and moral beliefs.

9. Activity 2.1.1: Chronicles of a Genetic Counselor Introduction • Scientists have worked tirelessly to decode our genetic code. The goals of the Human Genome Project were to determine the sequence of the three billion base pairs that make up human DNA, identify all of the genes, and devise a method to store and analyze all of the data. The completion of this project in 2003 gave us the “parts list” for a human being. While scientists are still working to figure out how all of these parts fit together, they have learned the specific function of many genes in our genetic code, as well as how these genes determine traits and sometimes even signal disease.

10. Activity 2.1.1: Chronicles of a Genetic Counselor Introduction • Our genome consists of over three billion base pairs. Surprisingly, less than one percent of these A’s, C’s, G’s and T’s differ from person to person. Differences in our DNA help code for our unique appearance, personality, traits, and even our susceptibility to disease. Genetic diseases and disorders are illnesses that originate in our chromosomes and DNA. These genetic changes can be passed down from parent to child. Modern biology has given scientists the tools to examine changes in our DNA and to test for the presence of thousands of these genetic diseases.

11. Activity 2.1.1: Chronicles of a Genetic Counselor Introduction • Genetic testing is the use of molecular methods to determine if someone has a genetic disorder, will develop one, or is a carrier of a genetic illness. Genetic testing involves sampling a person’s DNA and examining the chromosomes or genes for abnormalities. The abnormality may be large – a large piece of a chromosome or a missing chromosome may be viewed under a microscope. Other abnormalities may be the result of a single base pair change – substitutions, deletions, or additions – in a single gene. Information from the Human Genome Project is expanding the uses of genetic testing to examine not only reproductive risks, but adult-onset conditions such as Huntington’s disease, mental illness, and even cancer.

12. Activity 2.1.1: Chronicles of a Genetic Counselor Introduction • In this activity, you are in the final steps of your training to become a genetic counselor. As a practical exam, you are asked to chronicle the case of one of your clients. Your notes on the case should showcase your expertise, your compassion, and your ability to provide clear, understandable options and advice. You will be assessed on the depth of your research, the sensitivity you show towards your client and the thoroughness of your analysis and recommendations. It is your final exam and you want to impress.

13. Student Response sheet • Fill out the survey. 3 minutes • Discuss at your table. Come up with 1 point you would like to share with the whole class. 2 minutes • Whole class discussion. 1 minute per group.

14. We will… • Come back to the questions from the survey later in the activity and later in the course.

15. Now you will • Take notes as I present the Genetic Disorders presentation. Record information on the Student Resource Sheet as I review the slides and show various video clips

16. What are Genetic Disorders? • Both environmental and genetic factors play a role in the development of disease. • A genetic disorder is a disease caused by abnormalities in an individual’s genetic material. • In this course, we will consider four different types of genetic disorders: • Single-gene • Multifactorial • Chromosomal • Mitochondrial

17. Single Gene Disorders • Single gene disorders are caused by changes or mutations that occur in the DNA sequence of one gene. • Remember that a gene, a segment of DNA, contains instructions for the production of a protein. • Diseases and disorders result when a gene is mutated resulting in a protein product that can no longer carry out its normal job.

18. Single Gene Disorders • Single gene disorders are inherited in recognizable patterns: • Autosomal dominant • Autosomal recessive • Sex linked • Genetic testing looks at genotype to determine if someone has a genetic disorder, will develop one, or is a carrier.

19. Review Question • A man and a woman are both carriers for sickle cell disease, an autosomal recessive trait. What is the risk of their having an affected child?

20. Answer • Each parent is heterozygous for the condition and has the genotype Ss (where “s” is the recessive sickle cell allele). Each parent passes one allele to the child, so there is a 25% chance that the child will have sickle cell disease. • Think back to PBS – what is sickle cell disease and what is life like for a person affected with this disorder?

21. Multifactorial Disorders • Multifactorial disorders are caused by a combination of environmental factors and mutations in multiple genes. • Development of heart disease is associated with multiple genes, as well as lifestyle and environmental factors. • Different genes that influence breast cancer development have been found on chromosomes 6, 11, 13, 14, 15, 17 & 22. • Many of the most common chronic illnesses are multifactorial.

23. Chromosomal Disorders • Humans have 46 chromosomes in their body cells. • 44 autosomes • 2 sex chromosomes • Because chromosomes carry genetic information, problems arise when there are missing or extra copies of genes, or breaks, deletions or rejoinings of chromosomes. • Karyotypes, pictures of the paired chromosomes of an individual, are important in diagnosing chromosomal disorders.

25. Mitochondrial Disorders • Mitochondria, the organelles in your cells that convert energy, also contain DNA. • A mitochondrial disorder, a relatively rare type of genetic disorder is caused by mutations in nonchromosomal DNA of mitochondria. • Mitochondiral DNA is unique in that it is passed solely from mother to child

26. Carrier Screening • Carrier screening determines whether an individual carries a copy of an altered gene for a particular recessive disease even though they do not show the trait phenotypically. • Carrier screening is often used if a particular disease is common in a couple’s ethnic background or if there is a family history of the disease. • Examples of carrier tests include those for Tay-Sachs disease or sickle cell disease.

27. Preimplantation Genetic Diagnosis (PGD) • PGD is used following in vitro fertilization to diagnose a genetic disease or condition before the embryo is implanted in the uterus. • A single cell is removed from an embryo and examined for chromosome abnormalities or genetic changes. • Parents and doctors can then choose which embryos to implant. • Secrets of the Sequence – Chosen Child video http://www.pubinfo.vcu.edu/secretsofthesequence/playlist_frame.asp

28. The Process of Preimplantation Genetic Diagnosis

29. Fetal Screening/Prenatal Diagnosis • Prenatal diagnosis allows parents to diagnose a genetic condition in their developing fetus. • Techniques such as amniocentesis, chorionic villi sampling (CVS), and regular scheduled ultrasound allow parents to monitor the health of the growing fetus.

30. Newborn Screening • The most widespread type of genetic screening, newborn screening is used to detect genetic or metabolic conditions for which early diagnosis and treatment are available. • State tests for newborns typically screen anywhere from 4 to over 30 genetic or metabolic disorders. • Testing protocol and mandates vary from state to state. • The goal of newborn screening is to identify affected newborns quickly in order to provide quick treatment and care.

31. Activity 2.1.1 • In this activity, you will assume the role of a genetic counselor and meet with clients faced with difficult decisions regarding genetic disorders and genetic testing. • Your goal is to effectively explain the disease or disorder to your clients as well as to outline potential options for genetic testing and screening and overall management of disease.

32. Success Check • 1. _________________ is the category of disorders that are passed only from Mother to child. • 2. _________________ is a category of disorders that involve missing or duplicated genes. • 3. Multifactoral disorders are caused by a combination of ________________ factors and mutations in multiple genes. • 4. Dominant, recessive or sex-linked are terms used when describing __________ ________ disorders.

33. Complete 2.1.1 Student Response sheet by • Work with a partner to match each of the disorders listed in Step 6 to one of the classifications of disorders presented in the presentation. Be specific about how this disease is inherited or passed on and whether or not this disorder is the result of abnormalities in a gene or on a chromosome. Think about how these abnormalities affect function and describe how the disease affects function. • Use the Internet to investigate the following genetic disorders. • Duchenne Muscular Dystrophy • Cystic Fibrosis • Huntington’s Disease • Down Syndrome • Leber hereditary optic neuropathy • Alzheimer’s Disease You have 25 minutes. If you complete it early – Complete the crossword! Otherwise the crossword is homework! Ahhhhh

34. What are the duties of a genetic counselor? • Part II • Use the Internet to research a career in genetic counseling. In your career journal, write a one paragraph job description for a genetic counselor. Be sure to properly cite your sources. • Using the list of genetic disorders you have investigated in Part I, brainstorm how a genetic counselor might help in the case of two of the disorders. Record your answers in your career journal. • Turn this in by the beginning of the period on WEDNESDAY!

35. Cracking the code of life • video clip Chapter 3 of 12: One Wrong Letter • PAY SPECIAL ATTENTION TO THE INHERITANCE OF TAY SACHS. • Draw a pedigree for the family on your dry erase boards. • Discuss with your table how a genetic counselor might have helped this family.

36. Case Files • Obtain a genetic counseling case file from your teacher. Each file provides background information on a person or a family that is seeking your advice and expertise. You will work on the case as a member of a team. • Silently read the genetic counseling case. Your team’s job is to investigate the disease or disorder in question and decide how to counsel the family. Remember, you are not telling them what to do. You are providing information and options as well as answering their questions. • Research the genetic disorder/condition of concern

37. With your partner(s) • Take notes in your laboratory journal as you research and discuss the illness. • Cite your sources.

38. What is the PRODUCT? • Your job is to produce the case notes or chronicles of a genetic counselor. A colleague should be able to pick up your notes, read your recommendations and be able to counsel the family. Impress your employer with how much you know! • #18 in the curriculum lets you know what you should include. • Case notes should be typed up.

39. Presenting • Come up with a unique way to present your information to the class. You will have five minutes.

40. Success Check • I think this case will be interesting because…. • I think that when we present our case, one of the biggest things the class will learn will be….