This web page was produced as an assignment for Genetics 564, an undergraduate capstone course at UW-Madison.
What is Homology?
Figure 1. Structural homology in forelimbs of vertebrates
Homology describes similarity between different organisms due to common ancestry. Homology can be seen in anatomical structures, genes and proteins of different organisms. A classic illustration of structural homology can be seen in Fig. 1 in the forelimbs of vertebrates. Protein homology can be determined using sequence similarity programs such as BLAST. Pictured below are organisms with homologous proteins to the human PINK1 protein.
PINK1 Homologs in Common Organisms
Pongo abelii (orangutan)
XP_002811395 98.80% identity |
C. elegans (Nematode worm)
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Discussion
It is expected that as evolutionary distance increases, percent identity decreases. This seems to hold true as mammals have a much higher percent identity to homo sapiens than non-mammal organisms. The PINK1 gene sequence is highly conserved in many species, providing many options for research using model organisms.
Homologs were confirmed using reciprocal BLASTs, Homologene, and Ensemble.
Homologs were confirmed using reciprocal BLASTs, Homologene, and Ensemble.
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