Wilson’s disease is inherited as a recessive autosomal trait. What is the probability of having sick children

Wilson’s disease is inherited as a recessive autosomal trait. What is the probability of having sick children in a family where one of the spouses suffers from the disease being analyzed.

Let us designate the gene that determines the development of Wilson’s disease as c, then the gene that determines the formation of normal copper metabolism in humans will be designated as C.

The spouse suffering from Wilson’s disease has a homozygous cc genotype, because the disease is phenotypically realized only if the genotype is homozygous. This person produces the same type of germ cells – с.

The second, healthy spouse can be both homo- and heterozygous. Let’s consider both options.

Let’s say a healthy spouse is homozygous – CC. It produces the same type of germ cells – C. All children will be healthy and heterozygous for the genotype – Cc. The chance of having a baby with Wilson’s disease is 0%.

Let’s say a healthy spouse is heterozygous – Cc. It produces germ cells of two types – c and C. The offspring is represented by the following variants: healthy children-heterozygotes (Cc) – 50%; children with Wilson’s disease (ss) – 50%.

Answer: in the case of heterozygosity of a healthy spouse for the considered criterion, the probability of having a sick child is 50%; in case of homozygosity – 0%.