How is analyzing the inheritance patterns of sickle cell disease through pedigrees allowed scientists to determine that the disease is autosomal recessive?

Analyzing the inheritance patterns of sickle cell disease through pedigrees allows scientists to observe the transmission of the trait across generations. In affected families, the disease appears in individuals only when both parents carry at least one copy of the recessive allele, which is consistent with an autosomal recessive inheritance pattern. This means that affected individuals have two copies of the mutated gene, while carriers have one normal and one mutated allele, and unaffected individuals have two normal alleles. Such patterns of inheritance help confirm that the disease is not sex-linked and follows the principles of Mendelian genetics.