SIMPLIFIED EXPLANATION OF PC GENES

I am not a doctor. I am not a scientist. I have no degrees or training in genetics. This is not in place of the many excellent resources available regarding genetics, but in response to several PC patient's comments that they don't understand this topic in relation to themselves, or 50/50 chance of their child having PC, or what some of the terminology means. Genetics is a very personal matter. The following is not a suggestion in any way of right or wrong or good or bad. It is simply an explanation of how genes work. Genetic Therapists specialize in talking with people about genetic inheritance. PC Project will be making these services available to PC Patients. Please let me know if the following helps, please improve it with your critique and comments.

 

  1. Every person has two copies of every kind of gene.
  2. PC is caused by one gene that isn't made exactly as it should be. A defect in a gene is called a 'mutation.' So PC is caused by a mutation in a single gene.
  3. For some diseases, there must be a mutation in both copies of the gene for the disease to appear. In PC only one of the pair has a mutation.  The gene that has the mutation is DOMINANT. That means is rules over the other gene. If a person has a mutation in one of the genes that cause PC, they will have the symptoms (thick nails, sore feet, etc.). The mutation for PC never 'hides' (recessive). If the mutation is there, a person will have PC. If a person does not have the symptoms, they do not have PC.
  4. Scientists have now identified all of the human genes. In 1995, Dr. Irwin McLean discovered the genes where mutations cause PC. These are keratin genes called K6a, K16, K6b, K17.
  5. Scientists have found that these four keratin genes pair up with K6a pairing with K16 in their functions and K6b pairing with K17 in their functions.
  6. When a baby is made, each parent gives one copy of every kind of gene to the baby. Remember, each person has two copies of every gene. A person with PC has one good copy and one copy with a mutation.
  7. If a person has PC, there is a  50/50 chance which copy of each gene will be passed to the child. The 50/50 rule doesn't change with how many children a person has. Every time a baby is conceived, it is the same 50/50 chance as to which copy of the gene will be passed to the baby. The baby will have eith two good copies or one good copy and one copy with the mutation.
  8. With some diseases, the inheritance pattern is different. The inheritance pattern in PC is called autosomal dominant. Autosomal means not involving one of the sex (male/female) genes and dominant because only one copy of the two copies has the mutation but that causes the symptoms.
  9. Genetic testing is presently an important step in learning more about PC. The discovery of the specific genes makes it meaningful to now carefully study PC patients through genetic testing and evaluation of their physical symptoms in the search for a cure. Scientists are discussing many possibile approaches, For example, a cure may come in a variety of ways, such as 'turning off' or "turning down" the gene with the mutation. PC Project is supporting and funding genetic testing in order to further research efforts to 'find a cure.'
  10.  The website has links to additional sources of information on genetics, gene testing, and other related issues. If you need some specific information or a referral, feel free to use the website email contact.

 

NOTE  - Genetic tests are available during pregnancy. Risks of these tests, personal decisions regarding what to do about the test results and other related questions are all important to discuss with qualified physicians and genetic counselors who have a broad understanding of these matters.