Recessive

Refers to the presence of a genetic disorder when inheriting two changed copies of a gene are needed for a person to show signs of the condition. In recessive inheritance of a gene on the X chromosome (“X-linked recessive inheritance”), males have only one copy of the X chromosome. Therefore, a mutation in a single copy of the gene is enough to cause the disorder. See autosomal recessive and X-linked recessive. Compare this term to dominant.