1. Karyotypes
BIO Predict offspring ratios based on a variety of inheritance patterns (including dominance, co-dominance, incomplete dominance, multiple alleles, and sex-linked traits).

2. Autosomes and Sex Chromosomes
Sex chromosomes contain genes that determine an organism’s sex (gender).
The remaining chromosomes that are not directly involved in determining the sex of an individual are called autosomes.
Organize them on a karyotype by the size of the chromosome and position of the centrosome.
Amniocentesis – removes amniotic fluid from around baby which can be used to organize a karyotype

3. Male and Female Karyotypes

4. Chromosome Abnormalities
Some disorders/syndromes can be discovered through a karyotype.
Chromosome Abnormalities derive from nondisjunction of chromosomes during meiosis.

5. Chromosome Abnormalities
Down Syndrome – 3 copies of chromosome #21 (trisomy 21)

6. Chromosome Abnormalities
Turner Syndrome – Female with only 1 X chromosome (XO) (monosomy x)

7. Chromosome Abnormalities
Klinefelter Syndrome – male with XXY

8. Chromosome Abnormalities
Patau Syndrome – 3 copies of #13

9. Pedigrees
BIO 3.2.2Predict offspring ratios based on a variety of inheritance patterns (including dominance, co-dominance, incomplete dominance, multiple alleles, and sex-linked traits).

10. Pedigrees
Geneticists use pedigrees to trace diseases or traits through families
Pedigrees are diagrams that reveal inheritance patterns of genes (traits/diseases)

11. Standard Symbols

12. How to label a Pedigree Is II-2 a male or a female?
Is IV-3 affected or unaffected?

13. Determining Inheritance Patterns
If trait or disease shows up in all generations, it is probably autosomal dominant.

14. Determining Inheritance Patterns
If the trait or disease usually skips generations, it is probably autosomal recessive.
If carriers are shown, or if a child has it and both parents do not, it is DEFINITELY recessive.

15. Determining Inheritance Patterns
If a trait is X-linked recessive it will usually only show up in males and will skip generations

16. Cystic Fibrosis – Recessive or Dominant?

17. This is one messed up pedigree!!!!

18. Polygenic Inheritance
Polygenic characters, such as skin color, are controlled by two or more genes.
Complex characters, such as polygenic traits, are influenced by both genes and environment.