What is an autosomal recessive inherited disease?
Children inherit one chromosome of a pair from each parent. The chromosome inherited from the father is a mix of his pair of chromosomes, and the one from the mother is a mix of her pair of chromosomes. We have 23 pairs of chromosomes in total, the structures which contain the large macromolecule DNA. DNA is a genetic code, or blueprint, for cells. It is arranged in sections, called genes, most of which contain the code for making proteins. There are therefore two copies of most genes. To cause NCL both copies of a gene must be faulty. This is why the NCLs are called autosomal recessive genetic diseases. Parents of children with NCL each have one faulty copy. To some of their children the healthy copy is passed on and to others the faulty copy is passed on. This is a completely random process. Children may therefore have two healthy copies, one healthy and one faulty copy, or two faulty copies. Only a child who inherits two faulty copies will develop NCL. For this type of inheritance t
