The analysis of variants generated by exome sequencing of families with rare Mendelian diseases is a time-consuming, manual process that represents one barrier to applying the technology routinely. To address this issue, we have developed a software tool, VAR-MD (http://research.nhgri.nih.gov/software/var-md/), for analyzing the DNA sequence variants produced by human exome sequencing. VAR-MD generates a ranked list of variants using predicted pathogenicity, Mendelian inheritance models, genotype quality and population variant frequency data.
Many non-synonymous single nucleotide polymorphisms (nsSNPs) are disease causing due to effects at protein-protein interfaces. We have integrated a database of the 3D structures of human protein/protein complexes and the humsavar database of nsSNPs. We analysed the location of nsSNPS in terms of their location in the protein core, at protein-protein interfaces and on the surface when not at an interface.
Information about genetic variation has been collected for some twenty years into registries, known as locus specific databases (LSDBs), which nowadays often contain information in addition to the actual genetic variation. Several issues have to be taken into account when considering establishing and maintaining LSDBs and these have been discussed previously in a number of articles describing guidelines and recommendations. This information is widely scattered and, for a newcomer, it would be difficult to obtain the latest information and guidance.
DNA sequence variation is the underlying basis of common human traits and rarer single-gene disorders. Understanding the variome, the variants in an individual's genome, is essential to enable the ultimate goals of personalized medicine. This critical research field has grown dramatically in recent years, mostly due to the spread and development of genotyping technologies.
Explosive growth in the generation of genotype-to-phenotype (G2P) data necessitates a concerted effort to tackle the logistical and informatics challenges this presents. The GEN2PHEN Project represents one such effort, with a broad strategy of uniting disparate G2P resources into a hybrid centralized-federated network.
Locus-Specific DataBases (LSDBs) store information on gene sequence variation associated with human phenotypes and are frequently used as a reference by researchers and clinicians. We developed the Leiden Open-source Variation Database (LOVD) as a platform-independent web-based LSDB-in-a-Box package. LOVD was designed to be easy to set up and maintain and follows the Human Genome Variation Society (HGVS) recommendations. Here we describe LOVD v.2.0, which adds enhanced flexibility and functionality and has the capacity to store sequence variants in multiple genes per patient.
The L1 syndrome is an X-linked recessive disease caused by mutations in the L1CAM gene. To date more than 200 different mutations have been reported, scattered over the entire gene, about 35% being missense mutations. Although it is tempting to consider these missense mutations as being disease-causing, one should be careful in drawing any firm conclusions, unless there is additional supporting information. This is in contrast to truncating mutations, which are always considered to be disease-causing, unless they involve truncations close to the gene stop codon.
Deep sequencing has shown that over 90% of human genes undergo alternative splicing. The splicing process requires exon-intron boundary recognition. SNPs located in the boundaries (splice sites) influence exon configuration. Also, splice site SNPs (ssSNPs) alter translation efficiency of the mRNA and lead to important changes in disease susceptibility. We developed the ssSNPTarget database to provide ssSNPs on human and mouse genes.
The neuronal voltage-gated sodium channel Nav1.1 encoded by the SCN1A gene plays an important role in the generation and propagation of action potentials in the central nervous system. Altered function of this channel due to mutations in SCN1A leads to hypersynchronous neuronal discharges resulting in seizures or migrainous attaques. A large number of distinct sequence variants in SCN1A are associated with diverse epilepsy and migraine syndromes. We developed an online and freely available database containing all reported sequence variants in SCN1A ().
G2P Knowledge Centre is part of GEN2PHEN and funded by the Health Thematic Area of the Cooperation Programme of the European Commission
within the VII Framework Programme for Research and Technological Development.