Exomes on the go – adventures with wANNOVAR

Going cloud. This post is about my most recent discovery when I was trying to modernize some of the bioinformatics tools that I had on my laptop. My experience with variant annotation is a good example of the latest trend in bioinformatics: replacing precise, but difficult-to-use tools by web-based convenience – I didn’t need to install anything after all. This is a brief journey into the world of variant annotation, taking advantage of my new favorite tool, wANNOVAR and applying it to the Epi4K dataset. Continue reading

TADA – a joint analysis of de novo and inherited risk factors in autism

Beyond de novo. One of the most robust ways to interpret exome data is the analysis of de novo mutations. However, in addition to the 1-2 de novo events that we can identify in every individual, there is a plethora of inherited variants that often look suspicious. Unfortunately, other than looking at monogenic recessive disorders, we are often incapable of understanding the importance of these inherited variants and tend to ignore them. A recent publication in Nature now overcomes this difficulty by applying a joint analysis of inherited and de novo variants in autism. Continue reading

The 1003 possible autism genes – a matter of constraint

Overview. There have been numerous publications on de novo mutations in autism and intellectual disability over the last three years. Many of these studies struggle to distinguish signal from noise, and the plethora of findings leaves the reader wondering which genes are bona fide autism genes and in which cases the evidence is limited. A recent paper in Nature Genetics uses a new metric to assess expected versus observed de novo mutations in more than published 1000 autism patient-parent trios – and the answers appear to be straightforward. Continue reading