Cystic fibrosis is an autosomal recessive trait on chromosome 7. This disorder affects chloride transport resulting in abnormal mucus production. This lifelong illness usually gets more severe with age and can affect both males and females. Symptoms and severity differ from person to person. Cystic fibrosis is the most common fatal inherited disease among whites and the major cause of chronic lung disease in children. 50% of people are expected to live to be 30, but a majority die before age thirteen. 1:2000 whites have cystic fibrosis, 1:17000 blacks, 1:6000 live births, 1:2500 Americans, and 1:20 is a carrier.
The genes are inherited in pairs, with one gene coming from each parent to make the pair. Cystic fibrosis occurs when both genes have mutations. A person with cystic fibrosis receives one cystic fibrosis gene from each parent. The parents of a child, with cystic fibrosis, each carry one nonworking copy of the gene and one working copy of the gene.
The parents are called cystic fibrosis carriers, and because they have one working gene they have no symptoms. Carrier parents have 1:4 chance to have a child who is a noncarrier of cystic fibrosis, a 1:2 chance to have a child who carries the gene, and a 1:4 chance with each pregnancy to have an affected child. If you have a son or daughter with cystic fibrosis, then you have a 1:1 chance of being a carrier. If you have a brother or sister with CF, you have a 2:3 chance of being a carrier. If you have a niece or nephew with CF, you have a 1:2 chance of being a carrier. If you have an aunt or uncle with CF, you have a 1:3 chance of being a carrier and a 1:4 chance if you have a...