BIOL 190 Lecture Notes - Lecture 21: Zygosity, Mendelian Inheritance, Human Genome
Document Summary
Gene linkage: genes that are close together on a chromosome are said to be linked rarely sort independently in meiosis. Recombination: production of gametes with allelic con gurations not present in either of the parental gametes that formed the individual, occurs through. Inter-chromosomal recombination: crossing over intra-chromosomal recombination, occurs during prophase 1, occurs between synapsis (paired homolog, new combinations of alleles are created. Incomplete: genes sort together more than 50% of the time but less than 100% of the time, complete, genes sort together 100% of the time. Linkage is generally incomplete because crossing over does occur during meiosis. Linkage disequilibrium: non-random association between dna sequences, human genome consists of many ld blocks where alleles stick. Inherited together more often than would be expected together: called areas of high linkage equilibrium. Interspersed with areas of low linkage equilibrium: cis - two dominant or recessive alleles are in each chromosome, ab/ab.