Human genetic variation is the genetic differences both within and among populations. There may be multiple variants of any given gene in the human population (genes), leading to polymorphism. Many genes are not polymorphic, meaning that only a single allele is present in the population: the gene is then said to be fixed.
Expense of the blood glucose test strips. Over time, test strips are often the most expensive part of monitoring your blood sugar, so keep in mind the cost of compatible strips when choosing your glucose monitor. On average, glucose test strips range from 35Â¢ to $1.00 each.
1 If not included, replacement retainers can cost $70-$250 for one or $140-$500 or more for a set. 2  Most dental insurance does not cover replacement retainers. 3  Removable Essix retainers made of vacuum-formed clear plastic typically cost $100-$250 for one or $200-$500 for a set. Vivera clear plastic retainers by Invisalign have an annual fee of $300-$750, for a new set of identical retainers delivered every three months. 2  Vivera retainers can be used by people whose teeth were straightened by conventional braces as well as those who used Invisalign's series of clear plastic aligner trays.