Three Mark Questions :
Give an example of an autosomal recessive trait in humans. Explain its pattern of inheritance with the help of a cross.

Autosomal recessive is one of several ways that a trait, disorder, or disease can be passed down through families. An autosomal recessive disorder means two copies of an abnormal gene must be present in order for the disease or trait to develop. Sickle Cell Anaemia is an autosomal recessive trait in humans. The genes responsible for this disease are located in autosomes. The disease being recessive, the trait should be present in homozygous condition, for it to express. People who carry a single copy of the gene are clinically normal but are carriers of the disease and can pass on the defective gene to their subsequent generation