3B4.3 Lesson - Analyzing Pedigrees

3B4.3 Lesson - Analyzing Pedigrees

• Affected - expresses the trait; has the trait and can pass the trait to offspring​

• Carrier - does not express the trait but can pass an allele for the trait to their offspring

• Normal - does not have the trait or carry the trait; not affected

​Dominant Traits

• NO CARRIERS

  • parent must be affected

Recessive Traits

• has carriers

  • can skip a generation

X-linked Recessive Traits

• more males affected than females

​BOXES are BOYS

Categorize

Options (3)

Has the trait ​

Does not have the trait ​

Does not have the trait but can pass it to offspring ​

Determine if the person expresses the trait.

Affected

Carrier

Normal

Multiple Choice

Which kinds of traits can skip a generation?

• Dominant
• Recessive

Multiple Choice

Which kinds of traits have carriers?

• Dominant
• Recessive

Autosomal Dominant Disorders

• AA - affected

• Aa - affected

• aa - unaffected

• Does not skip - Appears in every generation - may stop/end

• There are NO carriers

• At least one parent must be affected to give to the offspring.

• Affects both males and females equally.

Huntington's; Polydactyl; Achondroplasia;

​Autosomal Dominant Pedigrees

• ​AA = affected

• Aa = affected

• aa = normal

• NO CARRIERS

• Males and females equally affected

Labelling

Determine the genotypes

Drag labels to their correct position on the image

AA

Aa

aa

Autosomal Recessive Disorders

• aa - affected

• AA - normal

• Aa - carrier

• Can skip a generation.

• There are carriers.

• Unaffected parents can have affected offspring

• Can have male carriers

• Affects males and females equally

​Cystic Fibrosis, PKU, Tay-Sachs, Alzheimer’s, Sickle Cell

​Autosomal Recessive Pedigrees

• ​aa = affected

• Aa = carrier

• AA = normal

• Males and females equally affected

• Can have male and female carriers

Multiple Choice

If there are male carriers, then the inheritance pattern is

• autosomal recessive

• x-link recessive

• autosomal dominant

Labelling

Determine the genotypes.

Drag labels to their correct position on the image

aa

Aa

X-linked Recessive Disorders

• X^hX^h; X^hY - affected

• X^HX^h - carrier

• X^HX^H; X^HY - normal

• Can skip a generation.

• No male carriers

• Unaffected parents can have affected offspring

• Affects males more than females

• Females must inherit two recessive alleles to get it (X^hX^h)

• Males only need one recessive allele (X^hY)

• Affected mothers give trait to all sons

Red-green colorblindness; Hemophilia

​X-linked Recessive Pedigrees

• ​X^hX^h = affected female

• X^hY = affected male

• X^HX^h = carrier female

• X^HX^H = normal female

• X^HY = normal male

• Males affected more than females

• NO MALE CARRIERS

Labelling

Determine the genotypes.

Drag labels to their correct position on the image

XHXh

XHY

XhY

Multiple Choice

If a mother that has the trait gives it to all of her sons, then the inheritance pattern most likely is

• autosomal recessive

• x-link recessive

• autosomal dominant

Multiple Choice

If a mother that has the trait gives it to all of her sons, then the inheritance pattern most likely is

• autosomal recessive

• x-link recessive

• autosomal dominant