Showing posts with label QTL. Show all posts
Showing posts with label QTL. Show all posts

Wednesday, September 1, 2021

yeast quantitative genetics cross study

 


---

title: "yeast power study"

author: "H Qin"

date: "8/31/2021"

output:

  pdf_document: default

  html_document: default

---


```{r simulate genotypes}

rm(list=ls())

N = 150

nuc_means = rpois(10, lambda=10)

mit_means = rpois(15, lambda=10)

summary(nuc_means)

summary(mit_means)


b0= 0

b1= 1 # mito influence on phenotype

b2= 1 # nuclear influence on phenotype

b3 =0.2  # mit X nuc interaction influence on phenotype, p << 0.001

b3 =0.1  # mit X nuc interaction influence on phenotype, p=0.049

#b3 = 0.05 # p = 0.3

```


```{r simulate-phenotype}

debug = 0


phenotype_mit_nuc = function(b0, b1, b2, b3, mit_single_mean, nuc_single_mean, debug){

  y = b0 + b1*mit_single_mean + b2*nuc_single_mean + b3*mit_single_mean * nuc_single_mean

  if (debug > 0) {

    print( paste("pmn:: mit_single_mean =", mit_single_mean, "nuc_single_mean", nuc_single_mean) )

  }

  return (y)

}


nuc_genotypes = sample(1:10, N, replace=TRUE)

mit_genotypes = sample(1:15, N, replace=TRUE)

y = 1:N

for ( i in 1:N ){

  #print(paste("i:", i, "mit_genotypes[i]",mit_genotypes[i] ))

  y[i] = phenotype_mit_nuc(b0, b1, b2, b3, mit_means[mit_genotypes[i]], nuc_means[nuc_genotypes[i]], debug=0) + rnorm(1)

}  


tb = data.frame( cbind( y, mit_genotypes, nuc_genotypes)) 

tb$mit_genotypes = factor( tb$mit_genotypes)

tb$nuc_genotypes = factor( tb$nuc_genotypes)

summary(tb)

```


```{r}

library(nlme);


m1a = glm(y ~ mit_genotypes  , tb, family='gaussian');


m2 = glm(y ~ mit_genotypes + nuc_genotypes , tb, family='gaussian');


m3 =  glm( y ~ mit_genotypes + nuc_genotypes + mit_genotypes:nuc_genotypes, data=tb)

```


```{r}

#summary(m1a)

```


```{r}

anova( m1a, m2, test='F')

```


```{r}

summary(m2)

summary(m3)

anova(m2, m3, test='F')

```


Saturday, December 9, 2017

mouse phenome database, xiong11 dataset and qtlcurve


Xiong11: A flexible estimating equations approach for mapping function-valued traits - circadian mouse behavioral data in C57BL/6J and 129S1/SvImJ backcross (2011)

Xiong H, Goulding EH, Carlson EJ, Tecott LH, McCulloch CE, Sen S. A flexible estimating equations approach for mapping function-valued traits. Genetics. 2011 Sep;189(1):305-16. Epub 
2011 Jul 29.   PubMed 21705752     FullText









https://phenome.jax.org/projects/Xiong1


https://bitbucket.org/linen/qtlcurve

Function phenotype


Saturday, June 22, 2013

From gene interactions to QTL

Gene interaction network can be generalized as genetic interaction. Network reliability can be extrapolate to model fitness, and may offer an opportunity to study how product form of gene interaction can be translated to additive form of gene interaction in QTL.

Friday, June 21, 2013

Survivorship and QTL for a limiting aging locus in serial configuration with the rest of the network



 On 2013 June 25, I realized a mistake in E(t)_net, and it is not a simple sum of the two serial components.

Note that S'(t) = S(t) * mu(t)
Comparison of the two form can explain the so-called missing heritability.

How about the variance? 




Thursday, June 20, 2013

Bloom et al, 2013 Nature, missing heritability in a yeast cross, BYxRM (in progress)

Finding the sources of missing heritability in a yeast cross
Joshua S. Bloom1,2, Ian M. Ehrenreich1,3, Wesley T. Loo1,2, Thu´y-Lan Vo˜ Lite1,2 & Leonid Kruglyak1,4,5
Nature, 2013

Bloom13 measured 1008 haploid segregants from a BYxRM cross. All strains are genotyped by deep sequencing. 30.6K SNPs were identified, which is about 0.5%. 

Bloom13 stated that difference between broad sense heritability H^2 and narrow sense heritability h^2 is due to gene-gene interaction. Bloom13 showed that most additive heritability are explained by detected QTL. (This is somewhat expected, isn't it? This is what linear regression is designed for.). 

Bloom13 provided their raw data and code. This is a great effort. 

There are several reviews and comments on this publication. One comment is on the 50% allele frequency in this controlled study. Both Brookfield13 and Bloom13 seem to define missing heritability 



Reference
http://genomics-pubs.princeton.edu/YeastCross_BYxRM/
Brookfield, 2013, Current biology, Quantitative Genetics: Heritability Is Not Always Missing

Wednesday, June 12, 2013

Interacting loci and QTL in network model of aging



Complex system configuration can be addressed by state vectors.

See PPT slides of J. Akipelu.