Life Science Group
DNA molecular basis of sequence variation
Sources of variation
According to the study, can be divided into two types of mutation : variation on the variation and groups on individual variation in the population is associated with research, EG drinking crowd vs non-drinking crowd compared.
Causing mutation three mechanisms:
1.DNA replication: DNA replication enzymes error
DNA replication instrinsic polymerase errors
Activities of error-prone polymerase: skip damage repair
2.DNA damage
Endogenously induced DNA damages。
Endogenously induced damages: plants than animals exposed to ultraviolet light longer, so for UV-induced damage is very strong.
3.Repair mechanism：
Global repair: start from the origin of replication repair.
Recombination : EG : Cluster fall into the gene will be destroyed
Repair TCR : translesion skip damage repair
Different types of injury: Base excision Repair | mismatch The | nucleotide excision Repair
DNA relationship between damage and repair damage after the act is: STOP Copy | Copy No | change Transport | Repair .
Different damage can lead to different repair: The reason - injury - Repair
Fertilized egg whole process mutation , i.e., De Novo mutation , abbreviated DNM .
Factors: Parents Age | A parent Variety | Parental both-haplotype haploid exist | mosaicism chimeras exist | paternal than maternal haploid haploid mutation high.