Factor Five Leiden


A DNA molecule is made up of amino acid chains called proteins. DNA carries the information needed to cause protein synthesis and replication. Replication is the way DNA copies itself for each descendent cell or virus, thus passing the information through our genes. A gene is basically a protein molecule made up of amino acids. The order in which these proteins are placed is specified by a sequence of DNA nucleotide's. If you change one DNA nucleotide with another one that has a different base, or make up, then this will cause all further cells, or descendent cells and viruses, to have the different make up. This change in the DNA molecule is called a mutation, this change can take place as a error during the replication process. This is exactly what we see with the Factor Five mutation.

The normal factor five gene code is G1691A. However, the code for FVL is G1691G. See where the mutation is? The A (arginine) was changed to an G (glutamine). This one change in the amino acid chain, or factor five protein, will now cause all descendent cells to replicate with this mutation. If we get one of these mutated genes from just one of our parents, then we will be heterozygous. We will have a 50% chance of passing the mutation on to our offspring. If we get one mutated gene from each parent, then we will have double heredity and be homozygous. You can only get one gene from each parent. We all have two genes and each parent will pass one of their two genes on to you. So, if you are homozygous and you have two mutated genes then all you have to pass on is a mutated gene. This means than that if one parent is negative for FVL and the other parent is homozygous for FVL than all the offspring will be heterozygous. They will all be single heredity.