Sir Kenneth Mather Memorial Prize 2012/13 – Xianchi Xin
Xianchi Xin (University of Edinburgh)
I am very delighted to have been awarded the Sir Kenneth Mather Memorial Prize in 2013 and would like to show my gratitude to my MSc programme director Professor Andrew Leigh-Brown for the nomination and the Genetics Society for the prize. I also want to thank Professor Chris Haley, Dr Pau Navarro and Dr Carmen Amador, who offered great help during the supervision of my MSc project.
My MSc project was titled ‘Capturing the Genomic Heritability of Complex Traits’, in which I explored the impacts of the allele frequency spectrum of SNP array, marker density, chromosome length and the complexity of relationship of the population on heritability estimation for human complex traits, including height, BMI and HDL, using GREML approach in a Scottish cohort comprising of ~10,000 individuals genotyped for ~700,000 SNPs. I found that height, BMI and HDL nicely follow the infinitesimal model as the per chromosome-based heritability estimates are proportional to the chromosome lengths and SNPs with different allele frequency spectrum seem to have the same contribution to the genetic variance. I also discovered that the SNP-based heritability will increase if we include related individuals in the analysis (compared to SNP-based heritability obtained from unrelated population), indicating the existence of extra variation (either genetics or environment) shared among close relatives, which probably can explain some missing heritability. In addition, a SNP array with a mark density of one SNP per 6Kb is sufficient to capture all SNP-based heritability in our population for these traits.
Currently, I am a PhD student under the supervision of Professor Chris Haley and Dr Pau Navarro in MRC IGMM, University of Edinburgh, working on exploring the architecture of human complex trait variation related to anthropometric and cardiometabolic traits in the same cohort.