This type of inheritance is called autosomal recessive. Autosomal means that the gene is on one of the first 22 pairs of chromosomes which do not determine gender, so that the disease equally affects males and females. Recessive means that two copies of the gene, one inherited from each parent, are necessary to have the condition. Many autosomal recessive conditions occur this way. Since both parents are healthy, they had no prior knowledge that they carried the gene, nor that they passed the gene to the pregnancy at the same time.
Genes are founds on structures in the cells of our body called chromosomes.
There are normally 46 total, or 23 pairs of chromosomes in each cell of our body. This gene is quite large and complex. Laboratories generally test for the most common mutations, and most labs test for anywhere from 30 to 100 total mutations. The detection rate depends on the person s ethnic background. The detection rate differs because CF is more common in certain geographical areas and certain populations of the world.