Transcript Pedigrees - Los Gatos High School

Pedigrees
Complex Inheritance Patterns:
Autosomal v. X-Linked
• Family Tree
• Genealogy
• Inheritance Diagram
• Relates parents and offspring for numerous generations
• Shows relationships between parents, children,
grandchildren…
• Aunts, uncles; cousins; second-cousins; distant relatives
• Are useful in tracking complex inheritance traits,
genetic disorders, and sex-linked traits
Pedigree
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Female: Circle
Male: Square
Line between: Parental relationship
Line down: Parent to children
Line over and connecting: Siblings
• Chronological order: Left to Right
• Left (oldest) to right (youngest)
• Dashed Line: Same person
• Shading: Carries/has specific trait
How to make a pedigree
My Pedigree: Eye Color
Tibbot
Csik
(bb)
Cindy
Csik
(bb)
Phil
Csik
(Bb)
Dottie
Csik
(Bb)
Terry
Csik
(Bb)
Paul
Csik
(Bb)
Jerry
Vessey
(bg)
Steven
Csik
(bb)
Phil
Csik
(Bb)
Genell
Csik
(gg)
Kirstin
Csik
(Bg)
Diane
Vessey
(gg)
Nick
Csik
(Bg)
Corinne
Popke
(bg)
• Please get out Investigation 18: Punnett Square Practice
• We already did Parts A, B and C last week
• SKIP the Analysis Questions
• Do Part D now
Let’s Practice!
Using Pedigrees
Solving problems for Sex-linked traits, genetic
disorders and unknown inheritance
• A “sex-linked” trait is carried on one of the sex
chromosomes
• X-linked traits are far more common in men than women
• Tracking sex-linked traits, particularly when determining
if women are carriers, requires use of Pedigrees
Sex-linked traits
• Autosomes
• 22 homologous chromosome pairs
• Autosomal traits occur on one or more of
your AUTOSOMES
• Sex Chromosomes
• Sex-linked traits occur on a X or Y
• Female: XX
• Male: XY
Autosomal v. X-Linked
Albinos
http://www.animaltalk.us/albino-animals/
• Albino: Latin root meaning “white”
• Lack of pigment: no colors
• Autosomal, Recessive trait
AA=Normal
Aa=Carrier
aa=Albino
Autosomal Inheritance:
Albinism
• Ocular: Latin root meaning “Eye”
• Lack of pigment in eyes only
• X-Linked, Recessive trait
XX=Normal
Xx=Carrier
xx=Ocular Albino
XY=Normal
xY=Ocular Albino
X-Linked Inheritance:
Ocular Albinism
http://www.scientificamerican.com/article.cfm?id=cosmetics-animal-testing
http://ocw.tufts.edu/Content/51/lecturenotes/551169/551383
• Genetic bleeding disorder: No clotting factor
• IF you have hemophilia:
• No clotting proteins to work with platelets
• Recessive
• Rare disease
• X-Linked
• More common in males
• VERY rare in females
Hemophilia
http://www.zimbio.com/Hemophilia/articles/Tds3gpcOOph/Hemophilia+Disease
• We will be taking on roles today to help solve the
mystery of the Russian Royal family, and the would-be
heir: Alexei Romanova
• We will construct a pedigree of the Victorian-era royal
family to help us investigate the mysterious deaths of
royals
The Romanova Mystery