Sickle-Cell Anemia is an example of an autosomal recessive genetic disorder. If two unaffected parents have 3 offspring, 2 of which do not have the disorder, and 1 who does, what must the parents Genotypes be?

Let 'A' denote a normal, non-faulty allele, such that the individual does not have sickle cell anemia Let 'a' denote a faulty allele, such that the individual has sickle cell anemiaAs neither parent has the disorder, both parents must possess at least 1 normal allele (A). We can see that one of the parent's offspring has the genetic disorder, and therefore must be homozygous recessive (aa). As one allele comes from each parent, we can therefore deduce that both parents must be heterozygous (Aa)