International Biometric Society
ESTIMATING RELATEDNESS USING GENETIC MARKER DATA: APPLICATION TO DISEASE GENE
MAPPING
Anne-Louise Leutenegger 1,2, Emmanuelle Génin 3,4
1. Inserm, U946, Paris, France
2. Univ Paris Diderot, France
3. Inserm, U1078, Brest, France
4. Univ Bretagne Occidentale, France
Individuals are related if they share at least one common ancestor. The genetic
consequence of this shared ancestry is that alleles may be received identical by descent
(IBD) from an ancestor. These IBD alleles may be shared between individuals (relatedness)
and within an individual (inbreeding). Estimating relatedness and inbreeding has been done
historically relying on relationship (pedigree) information. Over the recent years, the
developments of high throughput technologies have made it possible to obtain large amount
of information from the genome (up to millions of markers nowadays) creating much interest
in performing such estimation from the genome.
We will first present how this dense genomic information can be exploited to estimate
relatedness and inbreeding. We will describe the models currently used in human genetics
and their relative merits. We will also show the difference in the information provided by
pedigrees and genomes.
We will then present how these developments have been of interest for disease gene
mapping. In linkage studies, it allows testing for linkage without known pedigrees. We will
show the examples of searching for rare recessive variants via homozygosity mapping from
consanguineous cases or from case-control data. In association studies, we will show how it
allows controlling for cryptic relatedness.
International Biometric Conference, Florence, ITALY, 6 – 11 July 2014