Last data update: 2014.03.03

R: Kinship coefficient and genetic index of familiality
gifR Documentation

Kinship coefficient and genetic index of familiality

Description

The genetic index of familality is defined as the mean kinship between all pairs of individuals in a set multiplied by 100,000. Formally, it is defined as

100,000 x 2/[n(n-1)]∑_(i=1)^(n-1)∑_(j=i+1)^n k_(ij)

where n is the number of individuals in the set and k_{ij} is the kinship coefficient between individuals i and j.

The scaling is purely for convenience of presentation.

Usage

gif(data,gifset)

Arguments

data

the trio data of a pedigree

gifset

a subgroup of pedigree members

Value

The returned value is a list containing:

gifval

the genetic index of familiarity

References

Gholami K, Thomas A (1994) A linear time algorithm for calculation of multiple pairwise kinship coefficients and genetic index of familiality. Comp Biomed Res 27:342-350

Note

Adapted from gif.c, testable with -Dexecutable as standalone program, which can be use for any pair of indidivuals

Author(s)

Alun Thomas, Jing Hua Zhao

See Also

pfc

Examples

## Not run: 
test<-c(
 5,      0,      0,
 1,      0,      0,
 9,      5,      1,
 6,      0,      0,
10,      9,      6,
15,      9,      6,
21,     10,     15,
 3,      0,      0,
18,      3,     15,
23,     21,     18,
 2,      0,      0,
 4,      0,      0,
 7,      0,      0,
 8,      4,      7,
11,      5,      8,
12,      9,      6,
13,      9,      6,
14,      5,      8,
16,     14,      6,
17,     10,      2,
19,      9,     11,
20,     10,     13,
22,     21,     20)
test<-matrix(test,ncol=3,byrow=TRUE)
gif(test,gifset=c(20,21,22))

# all individuals
gif(test,gifset=1:23)

## End(Not run)

Results