Limits...
Where is the friend's home?

Chen GB - Front Genet (2014)

View Article: PubMed Central - PubMed

Affiliation: Centre of Neurogenetics and Statistical Genomics, Queensland Brain Institute, The University of Queensland St. Lucia, QLD, Australia.

AUTOMATICALLY GENERATED EXCERPT
Please rate it.

Christakis and Fowler reported that between friends there is positive/negative genetic correlation at the single nucleotide polymorphism (SNP) level, indicating heritability of friendship... This result is very interesting, particularly for the social sciences (Skyrms et al., ), but deserves scrutiny... Even if friendship is not heritable and relatives are not included, friends can still have inflated/deflated genetic correlation, which raises the regression coefficient from zero, if an ego finds friends from the same/different cultural background... If an ego finds friends from the same cultural background, pe(s) will be similar to pf(s)... Thus, the median of Fst was between the egos and the friends (n = 907 in Christakis and Fowler's study)... However, as long as friendship is more frequently established within one's cultural background, Fst will inflate genetic similarity among friendships even in the absence of heritability/“functional kin. ” With an increased sample size, λGC In the discussed study, the negative genetic correlation between friends was also highlighted... Similarly, if an ego finds friends from a different cultural background, the regression coefficient will tend to turn negative (denoted as st, indicating reduced genetic similarity between friends, see the yellow box in Figure 1)... In their GWAS-like analysis, principle components were used as covariates to control for Fst... However, covariates may not completely eliminate the background effects, such as Fst... When covariates reduce Fst, the heritability of friendship will also be reduced, potentially to zero... Although the analysis in this note does not entail the rejection of the conclusion drawn by Christakis and Fowler, it warns against misleading interpretations of the results.

No MeSH data available.


Illustration of how an ego-friend from the same/different subgroup(s) may inflate/deflate genetic similarity as indicated by λGC.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4230179&req=5

Figure 1: Illustration of how an ego-friend from the same/different subgroup(s) may inflate/deflate genetic similarity as indicated by λGC.

Mentions: in which ge.m and gf.m are the genotypes of “ego” and his/her friend, respectively, at the mth locus (m = 1, 2, 3 … M). The regression coefficient is estimated as . In a conventional GWAS regression, the phenotype is the same for each locus, whereas in this regression, the ge.m phenotype is updated to match each gf.m locus. However, this actually models Fst under the circumstances as discussed below (blue box in Figure 1). For clarity, the subscript m is hereafter omitted.


Where is the friend's home?

Chen GB - Front Genet (2014)

Illustration of how an ego-friend from the same/different subgroup(s) may inflate/deflate genetic similarity as indicated by λGC.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4230179&req=5

Figure 1: Illustration of how an ego-friend from the same/different subgroup(s) may inflate/deflate genetic similarity as indicated by λGC.
Mentions: in which ge.m and gf.m are the genotypes of “ego” and his/her friend, respectively, at the mth locus (m = 1, 2, 3 … M). The regression coefficient is estimated as . In a conventional GWAS regression, the phenotype is the same for each locus, whereas in this regression, the ge.m phenotype is updated to match each gf.m locus. However, this actually models Fst under the circumstances as discussed below (blue box in Figure 1). For clarity, the subscript m is hereafter omitted.

View Article: PubMed Central - PubMed

Affiliation: Centre of Neurogenetics and Statistical Genomics, Queensland Brain Institute, The University of Queensland St. Lucia, QLD, Australia.

AUTOMATICALLY GENERATED EXCERPT
Please rate it.

Christakis and Fowler reported that between friends there is positive/negative genetic correlation at the single nucleotide polymorphism (SNP) level, indicating heritability of friendship... This result is very interesting, particularly for the social sciences (Skyrms et al., ), but deserves scrutiny... Even if friendship is not heritable and relatives are not included, friends can still have inflated/deflated genetic correlation, which raises the regression coefficient from zero, if an ego finds friends from the same/different cultural background... If an ego finds friends from the same cultural background, pe(s) will be similar to pf(s)... Thus, the median of Fst was between the egos and the friends (n = 907 in Christakis and Fowler's study)... However, as long as friendship is more frequently established within one's cultural background, Fst will inflate genetic similarity among friendships even in the absence of heritability/“functional kin. ” With an increased sample size, λGC In the discussed study, the negative genetic correlation between friends was also highlighted... Similarly, if an ego finds friends from a different cultural background, the regression coefficient will tend to turn negative (denoted as st, indicating reduced genetic similarity between friends, see the yellow box in Figure 1)... In their GWAS-like analysis, principle components were used as covariates to control for Fst... However, covariates may not completely eliminate the background effects, such as Fst... When covariates reduce Fst, the heritability of friendship will also be reduced, potentially to zero... Although the analysis in this note does not entail the rejection of the conclusion drawn by Christakis and Fowler, it warns against misleading interpretations of the results.

No MeSH data available.