dominance

dominance

 [dom´ĭ-nans]

1. the supremacy, or superior manifestation, in a specific situation of one of two or more competitive or mutually antagonistic factors.

2. the appearance, in the phenotype of a heterozygote, of one of two mutually antagonistic parental characters.

Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

dom·i·nance

(dom'i-nănts),

The state of being dominant.

Farlex Partner Medical Dictionary © Farlex 2012

dominance

(dŏm′ə-nəns)

n.

The condition or fact of being dominant.

The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.

Genetics The ability of a dominant gene to express itself in a phenotype, when the gene is paired with another (recessive) gene that would have expressed itself in a different way
Neurology The tendency of one brain hemisphere to be more controlling than the other in mediating neural activity
Psychiatry A predisposition to playing the controlling role when interacting with others
Sexology See Domination
Transplant medicine See Donor dominance, Recipient dominance

Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.

dominance

Genetics The ability of a dominant gene to express itself in a phenotype, when the gene is paired with another (recessive) gene that would have expressed itself in a different way Neurology Cerebral dominance The tendency of one brain hemisphere to be more controlling than the other in mediating neural activity Psychiatry A predisposition to play a controlling role when interacting with others Sexology See Domination.

McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.

dom·i·nance

(dom'i-năns)

The state of being dominant.

Medical Dictionary for the Health Professions and Nursing © Farlex 2012

dominance

The power of a gene to exert its influence whether the other member of the gene pair is identical or dissimilar. GENES occur in pairs at corresponding positions (loci) on each of the paired CHROMOSOMES. A gene that has its effect only if paired with an ALLELE of the same kind is said to be RECESSIVE. The effect of a dominant gene paired with a recessive gene will be the same as if both genes had been identical to the dominant gene, but every cell in the affected person's body, including those producing sperms and eggs, contains the recessive gene. Such a person is said to be HETEROZYGOUS for that gene. When the sperms and eggs are produced, only one of the pair of chromosomes is included, so there is a 50/50 chance that this will be the one with the recessive gene. Should a sperm with the recessive gene fertilize an egg which also has the recessive gene, the recessive characteristic will be expressed because there is no other genetic material for the characteristic.

Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005

dominance

1. a genetic interaction where one ALLELE of a gene masks the expression of an alternative allele in the HETEROZYGOTE, so that the PHENOTYPE is of that form controlled by the dominant allele. For example, gene A has two alleles A1 and A 2:

1. but when heterozygous, A 1/ A2 = black phenotype. Thus A1 is dominant to A 2, with A2 ‘recessive’ to A1. In molecular terms, the A1 allele is coding for a protein of such quality and quantity to allow the normal amount of black pigment to be produced, even though the A2 allele is not coding for a normal enzyme. See also CODOMINANCE, INCOMPLETE DOMINANCE.
2. the preponderance of one species within an ecological COMMUNITY, for example, oaks in oak woods.

Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005