Post by Jian Yang on Oct 23, 2015 7:06:57 GMT
Bivariate GCTA-GREML of two independent samples
Here is an example of performing a bivariate GCTA-GREML analysis for two traits measured in two independent samples.
1) Creating a GRM for all the individuals combined (from the two samples)
2) Creating a phenotype file of two traits for all the samples. Assuming 100 individuals in sample #1 and 100 individuals in sample #2, here is an example of the phenotype file ("NA" represents missing data)
3) Note: this analysis also applies to a single trait measured in two samples. Then the analysis is to estimate genetic correlation between two samples for the same trait.
Here is an example of performing a bivariate GCTA-GREML analysis for two traits measured in two independent samples.
1) Creating a GRM for all the individuals combined (from the two samples)
2) Creating a phenotype file of two traits for all the samples. Assuming 100 individuals in sample #1 and 100 individuals in sample #2, here is an example of the phenotype file ("NA" represents missing data)
FID IID trait1 trait2
1 1 0.1 NA
2 2 0.2 NA
3 3 0.1 NA
…
100 100 0.5 NA
101 101 NA 2.1
102 102 NA 3.1
103 103 NA 2.2
…
200 200 NA 2.1
3) Note: this analysis also applies to a single trait measured in two samples. Then the analysis is to estimate genetic correlation between two samples for the same trait.