Yes, the disease, HCHWA-D, is hereditary. But how exactly does it work? What are the chances? And what if my children would like to have children?
It's in your genes" is an expression that applies to HCHWA-D. HCHWA-D is ‘inherited autosomal dominantly’. Following is an explanation of what this means from a biological perspective.
Chromosomes contain genes
Human beings are made up of a large number of cells. These cells contain chromosomes: 46 chromosomes (grouped in pairs). 23 from the father and 23 from the mother. These chromosomes contain genes.
Genetic predisposition is in the genes
A gene determines an inherited trait, like the colour of your eyes, hair etc. Every human body has about 25,000 genes, a few of which are abnormal. The effect of these ‘faulty’ genes goes totally unnoticed as the ‘malfunctioning’ of the abnormal genes is compensated for by the normal functioning gene on the other chromosome of the chromosome pair.
Defective HCHWA-D gene is non-compensable
The disease HCHWA-D is an abnormality on a chromosome. It is an abnormal gene. The problem is that the pattern of inheritance of HCHWA-D, is autosomal dominant. 'Dominant' means that the heritability factor of the abnormal gene - the disease- is stronger than the normal heritability factor. It dominates the normal construction of inheritance. Abnormality is, in this case, not compensated for by normality.
'Autosomal' means that the inclination to HCHWA-D is not dependant one a sex chromosome. Thus, the disease can occur as often in boys, as in girls.
Coincidence the determining factor
Lets suppose one parent is a carrier of the HCHWA-D gene. The defective gene is a part of one of the 23 chromosomes. If a child is conceived it randomly ‘receives’ 23 chromosomes from each is parent, including the chromosome that passes on the abnormal gene. There is therefore a 50% chance (1 out of 2) that a child of an affected parent will have the (predisposition of) the disease.
Can HCHWA -D skip a generation?
No. The disease can only be passed on if one (or both) of the parents are carriers. The disease can therefore not skip a generation. If you would like to know more about the genetic aspect of HCHWA-D and what the ‘50% chance’ means? make sure to read the detailed explanation on Inheriting HCHWA-D.
It is possible. You will then know for sure whether you have the genetic predisposition for HCHWA-D. Here you can find more on genetic testing and whether, or not, you would like to do it: Genetic testing to HCHWA -D.
Someone with the genetic predisposition of HCHWA-D has a 50% chance of passing on the disease to his or her children. But, there are other options. Explore these options.