Fine-scale estimation of location of birth from genome-wide single-nucleotide polymorphism data.

TitleFine-scale estimation of location of birth from genome-wide single-nucleotide polymorphism data.
Publication TypeJournal Article
Year of Publication2012
AuthorsHoggart CJ, O'Reilly PF, Kaakinen M, Zhang W, Chambers JC, Kooner JS, Coin LJM, Jarvelin M-R
JournalGenetics
Volume190
Issue2
Pagination669-77
Date Published2012 Feb
ISSN1943-2631
KeywordsAdult, Aged, Algorithms, Cohort Studies, Female, Finland, Genetics, Population, Genotype, Humans, London, Male, Middle Aged, Models, Statistical, Polymorphism, Single Nucleotide, Principal Component Analysis, Residence Characteristics
Abstract

Systematic nonrandom mating in populations results in genetic stratification and is predominantly caused by geographic separation, providing the opportunity to infer individuals' birthplace from genetic data. Such inference has been demonstrated for individuals' country of birth, but here we use data from the Northern Finland Birth Cohort 1966 (NFBC1966) to investigate the characteristics of genetic structure within a population and subsequently develop a method for inferring location to a finer scale. Principal component analysis (PCA) shows that while the first PCs are particularly informative for location, there is also location information in the higher-order PCs, but it cannot be captured by a linear model. We introduce a new method, pcLOCATE, which is able to exploit this information to improve the accuracy of location inference. pcLOCATE uses individuals' PC values to estimate the probability of birth in each town and then averages over all towns to give an estimated longitude and latitude of birth using a fully Bayesian model. We apply pcLOCATE to the NFBC1966 data to estimate parental birthplace, testing with successively more PCs and finding the model with the top 23 PCs most accurate, with a median distance of 23 km between the estimated and the true location. pcLOCATE predicts the most recent residence of NFBC1966 individuals to a median distance of 47 km. We also apply pcLOCATE to Indian individuals from the London Life Sciences Prospective Population Study (LOLIPOP) data, and find that birthplace is predicated to a median distance of 54 km from the true location. A method with such accuracy is potentially valuable in population genetics and forensics.

DOI10.1534/genetics.111.135657
Alternate JournalGenetics
PubMed ID22095078