How is factor VII deficiency inherited?

Factor VII deficiency is inherited in an autosomal recessive pattern. This means that for a person to exhibit symptoms of this deficiency, they must inherit two copies of the mutated gene, one from each parent. If a person has only one copy of the mutated gene, they are considered a carrier and typically do not show any clinical symptoms associated with the deficiency. This pattern of inheritance is characteristic of many coagulation factor deficiencies, reinforcing how important it is for both parents to contribute to the genetic risk of their offspring.

Knowing that factor VII is located on chromosome 13, it is evident that its inheritance does not follow X-linked or Y-linked patterns, which are associated with genes found on the sex chromosomes. This further validates why autosomal recessive is the correct answer in this context. Factors influencing the expression of Factor VII deficiency reflect the necessity of two affected alleles to manifest the disease, rather than a dominant inheritance model where a single affected allele could cause the disorder.