2. Klinefelter’s? Syndrome? Klinefelter’s? Syndrome? Klinefelter’s? Syndrome? Klinefelter’s? Syndrome? Klinefelter’s?

3. Chromosomal disorder

4. 1 every 550 males

5. Chromosomal disorder 1 every 550 males Additional X chromosome

6. Chromosomal disorder 1 every 550 males Additional X chromosome 47 XXY pair

7. Chromosomal disorder 1 every 550 males Additional X chromosome 47 XXY pair TESTES

8. Chromosomal disorder 1 every 550 males Additional X chromosome 47 XXY pair TESTES Don’t make enough testosterone

9. Chromosomal disorder 1 every 550 males Additional X chromosome 47 XXY pair TESTES Don’t make enough testosterone Don’t make any sperm

10. Chromosomal disorder 1 every 550 males Additional X chromosome 47 XXY pair TESTES Don’t make enough testosterone Don’t make any sperm Learning difficulties

11. Chromosomal disorder 1 every 550 males Additional X chromosome 47 XXY pair TESTES Don’t make enough testosterone Don’t make any sperm Learning difficulties Behavior difficulties

12. Chromosomal disorder 1 every 550 males Additional X chromosome 47 XXY pair TESTES Don’t make enough testosterone Don’t make any sperm Learning difficulties Behavior difficulties 3/10 diagnosed forever

13. Chromosomal disorder 1 every 550 males Additional X chromosome 47 XXY pair TESTES Don’t make enough testosterone Don’t make any sperm Learning difficulties Behavior difficulties 3/10 diagnosed forever Small testes

14. Chromosomal disorder 1 every 550 males Additional X chromosome 47 XXY pair TESTES Don’t make enough testosterone Don’t make any sperm Learning difficulties Behavior difficulties 3/10 diagnosed forever Small testes Need for testosterone replacement

15. Chromosomal disorder 1 every 550 males Additional X chromosome 47 XXY pair TESTES Don’t make enough testosterone Don’t make any sperm Learning difficulties Behavior difficulties 3/10 diagnosed forever Small testes Need for testosterone replacement Gel on skin or injection

16. Chromosomal disorder 1 every 550 males Additional X chromosome 47 XXY pair TESTES Don’t make enough testosterone Don’t make any sperm Learning difficulties Behavior difficulties 3/10 diagnosed forever Small testes Need for testosterone replacement Gel on skin or injection Muscle strength

17. Chromosomal disorder 1 every 550 males Additional X chromosome 47 XXY pair TESTES Don’t make enough testosterone Don’t make any sperm Learning difficulties Behavior difficulties 3/10 diagnosed forever Small testes Need for testosterone replacement Gel on skin or injection Muscle strength Body hair

18. Chromosomal disorder 1 every 550 males Additional X chromosome 47 XXY pair TESTES Don’t make enough testosterone Don’t make any sperm Learning difficulties Behavior difficulties 3/10 diagnosed forever Small testes Need for testosterone replacement Gel on skin or injection Muscle strength Body hair Strong bones

19. Chromosomal disorder 1 every 550 males Additional X chromosome 47 XXY pair TESTES Don’t make enough testosterone Don’t make any sperm Learning difficulties Behavior difficulties 3/10 diagnosed forever Small testes Need for testosterone replacement Gel on skin or injection Muscle strength Body hair Strong bones Less fat

20. Chromosomal disorder 1 every 550 males Additional X chromosome 47 XXY pair TESTES Don’t make enough testosterone Don’t make any sperm Learning difficulties Behavior difficulties 3/10 diagnosed forever Small testes Need for testosterone replacement Gel on skin or injection Muscle strength Body hair Strong bones Less fat INFERTILITY

21. Only the few...