Topic 4: Genetic Information: Measuring genetic biodiversity

Genetic biodiversity can be assessed by calculating the percentage of gene variants (alleles) in a genome within isolated populations.

A high genetic biodiversity means there is a large variety of alleles in the population's gene pool. Measuring genetic diversity also allows quantification of diversity within and between species

Genetic diversity can be compared by:

1. Comparing the frequency of measurable or observable characteristics

2. Comparing the base sequences of DNA

3. Comparing the base sequence of mRNA

4. Comparing the amino acid sequence of the proteins encoded by DNA and mRNA

Limitations of using observable characteristics to measure genetic diversity:

• Traits are often polygenic- meaning they are influenced by several genes, which makes it challenging to separate the influence of individual genes

• Environmental factors can alter traits - this leads to variations that are not genetically based

• Traits may change gradually across a range-traits not falling into distinct categories make them difficult to differentiate

Using comparative biochemistry to measure genetic diversity

Involves studying the molecular aspects of organisms to uncover genetic diversity

Useful molecules to compare genetic diversity:

• DNA-populations that are more genetically diverse will have more differences in their DNA sequences

• Messenger RNA - base sequences of mRNA are complementary to DNA so can assess genetic diversity

• Amino acids - populations that are genetically diverse will have more differences in their amino acid sequences because they are determined by mRNA and DNA