Paleness (pallor in Latin) is abnormal loss of color from normal skin or mucous membranes due to reduced amount of the blood in the skin arteries. Fair skin is genetically determined skin hue with low concentration of skin pigment (melanin) in the skin.
autosomal inheritance, a pattern of inheritance in which the transmission of traits depends on the presence or absence of certain alleles on the autosomes. The pattern may be dominant or recessive, and males and females are usually affected with equal frequency. The majority of hereditary disorders are the result of a defective gene on an autosome. Kinds of autosomal inheritance are autosomal-dominant inheritance and autosomal-recessive inheritance. See also inheritance.
Autosomal recessive diseases are genetic diseases that are passed to a child through both parents' chromosomes. Each person inherits 23 chromosomes from each parent and so has 23 pairs of chromosomes. Each chromosome contains genes. One or both of the chromosomes in a pair may contain a changed (mutated) gene that could cause a genetic disease. In an autosomal recessive disease, both chromosomes in a pair must have a changed gene for the person to have the disease. If only one chromosome has a changed gene, the person is a carrier and does not have symptoms.