BIOL 110 Lecture Notes - Lecture 16: Mendelian Inheritance, Generation Time, Zygosity

95 views2 pages
13 Oct 2015
School
Department
Course
BIOL110Lecture16PedigreeAnalysis
MendelianInheritanceinHumans
● Mendelianinheritanceinhumansisdifficulttostudy
○ Humansproducerelativelyfewoffspring
○ Humanshaveagenerationtimeofabout20years
■ Generationtimetimebetweenbirthofparentsandbirthofoffspring
○ Ethicalissues
● Thismakesitimpossibletodesignbreedingexperimentsinhumans
Pedigrees
UnderstandingofMendelianinheritanceisbasedonanalyzingmatingsthathave
alreadyoccurredthroughapedigree
● Pedigreesdescribetheinterrelationshipsbetweenparentsandchildrenovergenerations
regardingaspecifictrait
○ Mendel’slawsofinheritancecanbeusedtoanalyzethepedigreeandgenotypes
present
● Allowsgeneticisttounderstandthepastbutalsopredictoccurrenceofatraininfuture
generations
InheritanceofRecessiveTraits
● Carrierusedbecauseaheterozygousindividualmaycarryaparticularalleleinits
genotypebutnotexpressitinitsphenotype
○ Thisisseenwhentwotraitshaveacompletedominancerelationship
● Arecessivetraitisonlydisplayedinthephenotypeinhomozygousrecessiveindividuals
○ Phenotypicallynormalparentsmustbothbecarriers(heterozygous)forthe
diseasetooccurintheiroffspring
○ Anindividualmustinheritoneallelefromeachparents
● Diseasescausedbydeleteriousrecessivealleles
○ Cysticfibrosis
■ Adefectivegenealtersaproteinthatregulatesnormalmovementofsalt
inandoutofcell
■ Causesthick,stickysecretionsintherespiratoryanddigestivetracts
○ Phenylketonuria(PKU)
■ Normalallelecontainsinstructionsformakinganenzymeneededto
processtheaminoacidcalledphenylalanine,butthosesufferingfrom
phenylketonuriahavealleleswheretheenzymeisnotmaid
■ Causesdangerousbuildupofphenylalanine
■ CandevelopwhenapersonwithPKUeatsfoodsthatarehighinprotein
○ Sicklecelldisease
■ Disorderwherethegenethattellsthebodytomakehemoglobinis
mutated
Unlock document

This preview shows half of the first page of the document.
Unlock all 2 pages and 3 million more documents.

Already have an account? Log in

Get access

Grade+20% OFF
$8 USD/m$10 USD/m
Billed $96 USD annually
Grade+
Homework Help
Study Guides
Textbook Solutions
Class Notes
Textbook Notes
Booster Class
40 Verified Answers
Class+
$8 USD/m
Billed $96 USD annually
Class+
Homework Help
Study Guides
Textbook Solutions
Class Notes
Textbook Notes
Booster Class
30 Verified Answers