Pedigrees and Sex Linked Traits Outcome l I

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Pedigrees and Sex Linked Traits Outcome l I will explore how traits are inherited

Pedigrees and Sex Linked Traits Outcome l I will explore how traits are inherited through generations by solving autosomal and sexlinked pedigrees.

Sex Chromosomes l l l X and Y are sex chromosomes The other 22

Sex Chromosomes l l l X and Y are sex chromosomes The other 22 pairs are autosomal(body) chromosomes Males = XY Females = XX Not true homologous pairs – X has more genes

X and Y l Males – – l Get Y from dad Get X

X and Y l Males – – l Get Y from dad Get X from mom Females – – Get one X from dad Get one X from mom

Sex-linked traits l X-linked – The inheritance pattern of genes located on the X

Sex-linked traits l X-linked – The inheritance pattern of genes located on the X chromosome

Hemophilia Video l https: //www. phd. msu. edu/divisions/pediatricadolescent-hematology-oncology/educational -videos-about-hemophilia. html

Hemophilia Video l https: //www. phd. msu. edu/divisions/pediatricadolescent-hematology-oncology/educational -videos-about-hemophilia. html

X-Linked Punnett Square Sex linked H=normal & h=hemophilia Cross: XHXh x Xh. Y XH

X-Linked Punnett Square Sex linked H=normal & h=hemophilia Cross: XHXh x Xh. Y XH Xh Xh Xh Y H X Y h X Y • What is the chance that their son will have hemophilia? 50% • What is the chance that their daughter will have hemophilia? 50%

Sex-linked worksheet l l Working with your table, complete the sex linked worksheet in

Sex-linked worksheet l l Working with your table, complete the sex linked worksheet in your notes. You will have 6 minutes!

Pedigrees l a chart that shows how a trait (phenotype) is inherited through a

Pedigrees l a chart that shows how a trait (phenotype) is inherited through a family

Pedigrees l l circles: females squares: males shaded: individual with trait/disease Half-shaded: carriers for

Pedigrees l l circles: females squares: males shaded: individual with trait/disease Half-shaded: carriers for a trait but does not express the trait.

Generation / Individual Practice l l l Generations are the rows in a pedigree

Generation / Individual Practice l l l Generations are the rows in a pedigree Individuals are labeled across a pedigree Lines down represent offspring I 1 2 II 1 2 3 III 1 2 3 4

Quick Quiz l a. b. c. d. Individual A is A male who expresses

Quick Quiz l a. b. c. d. Individual A is A male who expresses the trait A female who does not express the trait A female who does express the trait What do we call this individual? Carrier

Quick Quiz l a. b. c. d. Individual D is A male who expresses

Quick Quiz l a. b. c. d. Individual D is A male who expresses the trait A female who does not express the trait A female who does express the trait

Quick Quiz l a. b. c. d. Individual H is A male who expresses

Quick Quiz l a. b. c. d. Individual H is A male who expresses the trait A female who does not express the trait A female who does express the trait

Outcome l I will explore how traits are inherited through generations by solving autosomal

Outcome l I will explore how traits are inherited through generations by solving autosomal and sexlinked pedigrees.

Fugates of Kentucky: Skin Bluer than Lake Louise l http: //www. youtube. com/watch? v=4

Fugates of Kentucky: Skin Bluer than Lake Louise l http: //www. youtube. com/watch? v=4 i. JVWMR 4 Uq 0

Fugates of Kentucky: Skin Bluer than Lake Louise l l l Methemoglobinemia blood disorder

Fugates of Kentucky: Skin Bluer than Lake Louise l l l Methemoglobinemia blood disorder with an abnormal amount of methemoglobin - a form of hemoglobin reduced ability to release oxygen to tissues - gives blood a bluish color

Autosomal Recessive l l Trait appears only when two parents by chance carry the

Autosomal Recessive l l Trait appears only when two parents by chance carry the hidden allele Affected individual inherits both recessive alleles Example: sickle cell disease Who could be a carrier?

Autosomal Dominant l l l Trait appears in every generation, in about half of

Autosomal Dominant l l l Trait appears in every generation, in about half of descendants (assuming a heterozygous carrier) Affected individual has at least one dominant allele Example: Huntington’s disease

X-linked Recessive l l Mother passes on to half of sons; half of daughters

X-linked Recessive l l Mother passes on to half of sons; half of daughters carry it. Father never passes on trait. Examples: Hemophilia, color blindness Why do more men have it? Who could be a carrier? Can men be carrier?

X-linked Dominant l l Father passes trait to all daughters; no sons. Mother passes

X-linked Dominant l l Father passes trait to all daughters; no sons. Mother passes on to half of children. Example: Rett syndrome

Outcome l I will explore how traits are inherited through generations by solving autosomal

Outcome l I will explore how traits are inherited through generations by solving autosomal and sexlinked pedigrees.