BIOL 222 Lecture Notes - Lecture 4: Meiosis, Albinism, Consanguinity
Document Summary
Biol 222 - lecture 4 - basic principles of heredity. Dihybrid cross - analyzing 2 genes simultaneously. Ry rryy rryy rryy rryy rryy ry rryy rryy. Rryy ( r)( y) = ry ( r)( y) = ry ( r)( y) = ry ( r)( y) = ry. Independent assortment - genes assort independently of one another (as long as they are on separate chromosomes. Gene pairs on different chromosomes assort independently during meiosis. Branch diagrams (for phenotypic ratios: list possibilities for one event, list probabilities of second event next to these, use product rule. P(aa bb cc dd ee) = ( )( )( )( )( ) = 1/256. ( c)( c) + ( c)( c) = cc. P(a-- bb c-- d-- ee) = ( )( )( )( )( ) = 27/1024. Mendelian inheritance of an autosomal recessive disorder is revealed by the appearance of the phenotype in male and female progeny of unaffected individuals.
