There are 3 number 21 chromosomes. This is called Trisomy 21

1. Analyze the karyotype: There are 3 number 21 chromosomes. This is called Trisomy 21 (tri:3, somy:body) Down Syndrome

2. Chapter 13 - Meiosis and Sexual Life Cycles AIM: What happens when meiosis goes wrong?

3. Chapter 13 - Meiosis and Sexual Life Cycles AIM: What happens when meiosis goes wrong? What about if non-disjunction occurs in the sex chromosomes?

4. Chapter 13 - Meiosis and Sexual Life Cycles AIM: What happens when meiosis goes wrong? Klinefelter’s Syndrome (XXY) - Sterile male typically - Female characteristics

5. Chapter 13 - Meiosis and Sexual Life Cycles AIM: What happens when meiosis goes wrong? XXXXY Klinefelter’s syndrome: can be any multiple of X with a single Y.

6. Chapter 13 - Meiosis and Sexual Life Cycles AIM: What happens when meiosis goes wrong? Turner Syndrome - Shorter stature (height) - Enlarged hands and feet - Underdeveloped ovaries (infertile) - Other problems (high blood pressure, heart problems, etc…)

7. Chapter 13 - Meiosis and Sexual Life Cycles AIM: What happens when meiosis goes wrong?

8. Chapter 13 - Meiosis and Sexual Life Cycles AIM: What happens when meiosis goes wrong? (normal for the most part)

9. Chapter 13 - Meiosis and Sexual Life Cycles AIM: What happens when meiosis goes wrong? What is the total number of chromosomes you would expect to find in a woman with Turner syndrome? 45, missing one X

10. Chapter 13 - Meiosis and Sexual Life Cycles AIM: What happens when meiosis goes wrong? Other mishaps can occur during meiosis resulting in chromosomal abnormalities that may cause disease. These abnormalities include… 1. Deletions 2. Duplications 3. Inversions 4. Translocations

11. Chapter 13 - Meiosis and Sexual Life Cycles AIM: What are some other ways chromosomes can be altered? There is a “mistake” made during meiosis resulting in the loss of a chromosome segment.

12. Chapter 13 - Meiosis and Sexual Life Cycles AIM: What are some other ways chromosomes can be altered? Diseases caused by deletions include: “cry of the cat” 1. Cri du chat - Cat-like cry - Low birth weight, cognitive (information processing) delays, motor (movement) and speech problems - Chromosome 5 deletion - Life span is normal

13. Chapter 13 - Meiosis and Sexual Life Cycles AIM: What are some other ways chromosomes can be altered? Diseases caused by deletions include: 2. Williams syndrome - Deletion of 26 genes in chromosome 7 - Elf like facial appearance - Unusually cheerful - Unpredictable negative outbursts - Mental retardation - Shortened life span due to narrowed arteries

14. Chapter 13 - Meiosis and Sexual Life Cycles AIM: What are some other ways chromosomes can be altered? Diseases caused by deletions include: 3. Duchenne’s muscular dystrophy i. Dystrophin gene - Largest gene in genome - 2.4 million base pairs!!!!!!!!! - Takes 16 hours to transcribe (to make a mRNA)!!!!!!! - Protein is 3500 amino acids! - X linked gene (means it is on the X-chromosome) - Function: connects muscle cell cytoskeleton to ECM (anchors cell to ECM)

15. Chapter 13 - Meiosis and Sexual Life Cycles AIM: What are some other ways chromosomes can be altered? Diseases caused by deletions include: 3. Duchenne’s muscular dystrophy ii. Symptoms begin at 2 to 6 years old iii. Develop muscle weakness and eventually failure iv. Wheelchair by age 12 v. Survival beyond 20 years old is rare vi. Affects 1 in 3500 MALES