GEN-3000 Lecture Notes - Lecture 7: Homologous Chromosome, Mendelian Inheritance, Karyotype
Document Summary
Morgan (morgan suggested that genes on same chromosome segregated together- also that closely linked were rarely subject to recombination. 1911: steurtevant generated first map of chromosomes based on recombination frequency. Review: principle of segregation- each diploid individual possesses two alleles that separated in meiosis, one allele to each gamete (each allele is at the same position on a homologous chromosome) Principle of independent assortment: two alleles separate independently of alleles at other loci. Chromosomes theory of heredity: sutton, genes are found on chromosomes. Linked genes: those that are close together on same chromosome. Travel together during meiosis, do not usually sort independently. In f2 generation: progeny do not appear in the 9:3:3:1 ratio expected with independent assortment. If genes are completely linked (no crossing over) With complete linkage, only nonrecombinant progeny are produced. If genes assort independently with independent assortment 1/2 progeny are recombinant 1/2 are not. With linked genes and some crossing over :
