chapters 11-12. * true-breeding * hybridization * p generation * f 1 generation * f 2 generation *...
TRANSCRIPT
Chapters 11-12
*Genetics
*Vocabulary
*True-breeding
*Hybridization
*P generation
*F1 generation
*F2 generation
*Alleles
*Dominant
*Recessive
*Homozygous
*Heterozygous (hybrid)
*Laws
*Law of segregation
*Law of independent assortment
*Laws of probability
*http://www.bozemanscience.com/probability-in-genetics
*Degrees of dominance
*Complete dominance
*Incomplete dominance
*Codominance
*Dominance and Phenotype
*Maybe recessive at organismal level, but codominant at molecular level
*Ex. Tay Sachs
*Multiple alleles
*Blood types
*Pleiotropy
*Genes may have multiple phenotypic effects
*Ex. Sickle cells, cystic fibrosis
*Epistasis
*A gene at one locus affects a gene at another locus
*Ex. Labrador retrievers p 217
*Polygenic inheritance
*Many genes involved
*Ex. Human skin color and height
*Nature and Nuture
*Multifactorial-may include genetic and environmental factors
*Ex. Heart disease, diabetes, cancer, alcholism, mental illnesses
*Pedigrees
*consanguineous
*To wed a cousin or not to wed, that is the question…
*Recessive disorders
*Albinism
*Cystic fibrosis 1/2500 of European descent (4% are carriers)
*Sickle Cell Anemia (1/400 African Americans) (2 allelesfull blown, but organismal level-incompletely dominant; heterozygotes have sickle trait-but may have trouble when oxygen low; molecularcodominant)
*Dominant Disorders
*Huntington’s Choreahttp://www.youtube.com/watch?v=65xf1olEpQM
*Achondroplasia
*Polydactyly
*Chromosome theory of
Inheritance
*Sutton, Boveri, et.al
*Mendelian genes have specific loci along chromosomes, and it is the chromosomes that undergo segregation and independent assortment
*Thomas Hunt Morgan
*Fly guy-Drosophila melanogaster
*Great experimental organism
*Small, large # of offspring, short life span, 8 chromosomes, easily observed traits
Phenotype most commonly observed in natural populations~wild type; alternatives~mutant phenotypes
Invented notation – use letter of first mutant discovered and wild is indicated with +
So, red eyes are dominant and the wild type: w+
White eyes were first mutant: w
*Sex-linked traits
*Sex chromosomes
*SRY-sex determining region of the Y
*Y-linked
*X-linked
*Sex linked recessive pedigree
*Sex Linked disorders
*Males can’t be carriers
*Males get it from Mom
*Males have it more often
*Color blindness
*Hemophilia-Royal disease (Queen Victoria)
*Duchenne muscular dystrophy
*X inactivation in Female Mammals
*One of the X chromosomes is inactivated in embryonic development
*Barr Body (Mary Lyon found it is random)-leads to a mosaic
*Tortoiseshell cat
*How X is inactivated
*Attach methyl groups to DNA
*On one X, XIST (X-inactive specific transcript) becomes activemakes RNA product that attaches to one andBarr body
*Linked genes
*http://www.youtube.com/watch?v=-_UcDhzjOio
*Aneuploidy
*Abnormal chromosome number
*Nondisjunction in anaphase I or II
*Monosomy
*Trisomy
*Polyploid
*Down syndrome
*Klinefelter
*Turner
*Alterations in chromosome
structure
*Deletion
*Duplication
*Inversion
*Translocation
*Disorders
*Cri du chat deletion of part of #5
*CML- chronic myelogenous leukemia reciprocal translocation between #9 and #22-shortened 22Philadelphia chromosome
*Genomic imprinting
*Angelmans syndrome http://www.angelman.org/understanding-as/diagnosis/
*Prader-Willi’s syndromehttp://www.youtube.com/watch?v=-6nzi5Rc4wY
*Decade of the genome: http://www.youtube.com/watch?v=Fgq-XoyorWY
*Hemophilia –the royal disease: http://www.youtube.com/watch?v=bmQwMllhCUM
*Other disorders: http://www.youtube.com/watch?v=l0dDhKFk2HU&list=PL199EFC951657FAA4&index=4
*Williams syndrome
http://www.youtube.com/watch?v=gF4DiqEdN3w
http://www.jeansforgenesday.org/disorders/childrensfilms