using gene technologies to assess genetic diversity

• genetic diversity is the number of different alleles in a population
• early estimates of genetic diversity were made by looking at the frequency of measurable or observable characteristics in a population

  e.g. the number of different eye colours in a population and the number of people with each particular eye colour
• since different alleles determine different characteristics a wide variety of each characteristic in a population indicates a high number of different alleles - and so a high genetic diversity
• gene technologies have now been developed that allow us to measure genetic diversity directly
• different alleles of the same gene will have slightly different DNA base sequences. Comparing the DNA base sequences of the same gene in different organisms in a population allows scientists to find out how many alleles of that gene there are in that population
• Different alleles will also produce slightly different mRNA base sequences and may produce proteins with slightly different amino acid sequences so these can also be compared
• These new technologies can be used to give more accurate estimates of genetic diversity within a population or species than can be made just by looking at the frequency of observable characteristics

  they also allow the genetic diversity of different species to be compared more easily