In genomic sequencing the sequence of nucleotide bases can be determined for individual genes and entire genomes.
Computer programs can be used to identify base sequences by looking for sequences similar to known genes.
Comparison of genomes from different species can be done by comparing sequence data.
→ To compare sequence data, computer and statistical analyses (bioinformatics) are required.
Comparison of genomes reveals that many genes are highly conserved across different organisms.
Many genomes have been sequenced, particularly of
There is evidence from phylogenetics and molecular clocks to determine the main sequence of events in evolution.
→ Phylogenetics is the study of evolutionary history and relationships.
→ Molecular clocks are used to show when species diverged during evolution.
→ Molecular clocks assume a constant mutation rate and show differences in DNA sequences or amino acid sequences.
→ Differences in sequence data between species indicate the time of divergence from a common ancestor, because molecular clocks assume a constant mutation rate and show differences in DNA sequences or amino acid sequences.
The main sequence of events in the evolution of life can be determined using sequence data and fossil evidence.
→ Sequence data is used to study the evolutionary relatedness among groups of organisms.
→ The main sequence of events of evolution (the order in which things evolved) is as below:
→ Sequence divergence is used to estimate time since lineages diverged.
Comparison of sequences provides evidence of the three domains of life — bacteria, archaea and eukaryotes.
An individual’s genome can be analysed to predict the likelihood of developing certain diseases
Genomic sequencing also has implications for pharmacogenetics and personalised medicine.
→ Pharmacogenetics is the use of genome information in the choice of drugs.
→ An individual’s personal genome sequence can be used to select the most effective drugs and dosage to treat their disease, which is personalised medicine.