1. Karyotypes& Chromosome Mutations

2. A karyotype is an organized profile of a person's chromosomes
A normal human karyotype has 46 chromosomes (23 pairs):
#1-22 are called autosomes
#23 are called sex chromosomes

3. XX~ female XY~ male

4. Chromosomal Mutations
Change in # of chromosomes OR structure of the chromosome
Mutations can only be inherited if they occur in sex cells

5. Can YOU spot the chromosomal mutation??

7. 1) Deletion
Loss of all or part of a chromosome

9. 2) Duplication
Produce extra copies of parts of a chromosome.

11. 3) Inversion
Part of a chromosome breaks out and reinserts backwards.

13. 4) Translocation
Part of a chromosome breaks off & attaches to another chromosome

14. 5) Nondisjunction
Improper separation of homologous chromosomes during meiosis
Results in extra or missing chromosomes in gametes

16. Remember—normally have 2 copies of each
Types of Nondisjunction
Trisomy~ 3 copies of a chromosome
Monosomy~ 1 copy of a chromosome
Remember—normally have 2 copies of each

17. Can you spot the mutation?

18. Down Syndrome – Trisomy 21
Intellectual and developmental disabilities
may have heart defects and respiratory problems

19. Look at the karyotype for the mutation

20. Trisomy on Sex Chromosomes
XYY Syndrome – Extra Y
XXX Syndrome – Triple X

21. What is the mutation?
Boy or Girl?

22. Trisomy 13 (Patau syndrome)
Extra fingers or toes
Cleft lip or palate (deformed lips)
Heart and brain structure problems
Die within 1-2 years of age

23. What is the mutation?
Boy or Girl?

24. Turner’s Syndrome 45,X Webbed neck Infertile
Swollen hands & feet at birth
Heart defects