| coefficient | 1. The expression of the amount or degree of any quality possessed by a substance, or of the degree of physical or chemical change normally occurring in that substance under stated conditions. 2. The ratio or factor that relates a quantity observed under one set of conditions to that observed under standard conditions, usually when all variables are either 1 or a simple power of 10. Origin: L. Co-+ efficio (exfacio), to accomplish (05 Mar 2000) |
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| coefficient of consanguinity | A statistical way of gauging how close two people are as to the genes. The coefficient of inbreeding (symbolised as F) is the probability that a person with two identical genes received both genes from an identical ancestor. Take first cousins who by definition share a set of grandparents. So for any particular allele (gene) in the father, the chance that the mother inherited the same allele from the same source is 1/8. Further, for any gene the father passes to his child, the chance is 1/8 that the mother has the same gene and 1/2 that she transmits that gene to the child so 1/8 X 1/2 = 1/16. Thus, a first-cousin marriage has a coefficient of inbreeding F =1/16. The added risks to the offspring of first cousins depend not only upon this coefficient of inbreeding but also upon the genetic family history and, in some cases, upon test results (for example, for beta thalassaemia for first cousins of Italian descent). However, there are always added risks from the mating of closely related persons and those risks are not negligible. (12 Dec 1998) |
| coefficient of inbreeding | A statistical way of gauging how close two people are as to the genes. The coefficient of inbreeding (symbolised as F) is the probability that a person with two identical genes received both genes from an identical ancestor. Take first cousins who by definition share a set of grandparents. So for any particular allele (gene) in the father, the chance that the mother inherited the same allele from the same source is 1/8. Further, for any gene the father passes to his child, the chance is 1/8 that the mother has the same gene and 1/2 that she transmits that gene to the child so 1/8 X 1/2 = 1/16. Thus, a first-cousin marriage has a coefficient of inbreeding F =1/16. The added risks to the offspring of first cousins depend not only upon this coefficient of inbreeding but also upon the genetic family history and, in some cases, upon test results (for example, for beta thalassaemia for first cousins of Italian descent). However, there are always added risks from the mating of closely related persons and those risks are not negligible. (12 Dec 1998) |
| coefficient of kinship | The probability that two genes at the same locus, picked at random from each of two individuals, are identical by descent. (05 Mar 2000) |
| coefficient of relationship | The probability that a gene present in one mate is also present in the other and is derived from the same source. (05 Mar 2000) |
| coefficient of variation | The ratio of the standard deviation to the mean. (05 Mar 2000) |
| coefficient of viscosity | The value of the force per unit area required to maintain a unit relative velocity between two parallel planes a unit distance apart. (05 Mar 2000) |