Article

Use of support vector machines for disease risk prediction in genome-wide association studies: Concerns and opportunities

Center for Bioinformatics Tuebingen (ZBIT), University of Tuebingen, Tübingen, Germany.
Human Mutation (Impact Factor: 5.14). 12/2012; 33(12). DOI: 10.1002/humu.22161
Source: PubMed

ABSTRACT

The success of genome-wide association studies (GWAS) in deciphering the genetic architecture of complex diseases has fueled the expectations whether the individual risk can also be quantified based on the genetic architecture. So far, disease risk prediction based on top-validated single-nucleotide polymorphisms (SNPs) showed little predictive value. Here, we applied a support vector machine (SVM) to Parkinson disease (PD) and type 1 diabetes (T1D), to show that apart from magnitude of effect size of risk variants, heritability of the disease also plays an important role in disease risk prediction. Furthermore, we performed a simulation study to show the role of uncommon (frequency 1-5%) as well as rare variants (frequency <1%) in disease etiology of complex diseases. Using a cross-validation model, we were able to achieve predictions with an area under the receiver operating characteristic curve (AUC) of ∼0.88 for T1D, highlighting the strong heritable component (∼90%). This is in contrast to PD, where we were unable to achieve a satisfactory prediction (AUC ∼0.56; heritability ∼38%). Our simulations showed that simultaneous inclusion of uncommon and rare variants in GWAS would eventually lead to feasible disease risk prediction for complex diseases such as PD. The used software is available at http://www.ra.cs.uni-tuebingen.de/software/MACLEAPS/.

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    • "Until now, the underlying genetic and molecular mechanisms of PD have not been completely understood. Mittag et al. showed in their study that it is not possible to predict the disease risk for PD with top-validated single-nucleotide polymorphisms, although such a prediction is possible for type 1 diabetes [8]. Thus, in the case of PD, genetic markers alone cannot explain the disease outbreak. "
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