The nature of mutations Point mutations: 1 Transitions(pyrimidine to pyrimidine, purine to purine) a 2. Transversions (pyrimidine to purine, purine to pyrimidine)
The nature of mutations Point mutations: 1. Transitions (pyrimidine to pyrimidine, purine to purine) 2. Transversions (pyrimidine to purine, purine to pyrimidine) Replication errors and replication
Insertions Deletions Gross rearrangement of chromosome These mutations might be caused by insertion by transposon or by aberrant action of cellular recombination processes
Insertions Deletions Gross rearrangement of chromosome. These mutations might be caused by insertion by transposon or by aberrant action of cellular recombination processes
Rate of spontaneous mutation at any given site on chromosomal ranges from 10-6 to 10-11 per round of DNA replication, with some sites being hotspot Mutation-prone sequence in human genome are repeats of simple di, tri or tetranucleotide sequences, known as dna microsatellites(微卫星DNA These sequences(1)are important in human genetics and disease, 2) hard to be copied accurately and highly polymorphic in the population
Rate of spontaneous mutation at any given site on chromosomal ranges from 10-6 to 10-11 per round of DNA replication, with some sites being “hotspot” . Mutation-prone sequence in human genome are repeats of simple di-, trior tetranucleotide sequences, known as DNA microsatellites (微卫星DNA). These sequences (1) are important in human genetics and disease, (2) hard to be copied accurately and highly polymorphic in the population
Each bases has its preferred tautomeric form(Related to Ch 9) 96oS9Sm amino imino H N N N H—Nf N keto enol H N N H H-bond donor H-bond acceptor Copyright o 2004 Pearson Education, Inc. publishing as Benjamin Cummings
Ch 6DNA STRUCTURE ( ) 2 Each bases has its preferred tautomeric form (Related to Ch 9)
The strictness of the rules for Waston-Crick"pairing derives from the complementarity both of shape and of hydrogen bonding properties between adenine and thymine and between guanine and cytosine N sugar sugar CH 3 N sugal sugar Copyright@ 2004 Pearson Education, Inc, publishing as Benjamin Cummings
The strictness of the rules for “Waston-Crick” pairing derives from the complementarity both of shape and of hydrogen bonding properties between adenine and thymine and between guanine and cytosine