euL1db: the European database of L1HS retrotransposon insertions in humans

Retrotransposonsaccount for almost half of our genome. They are mobile genetics elements—also known as jumping genes—but only the L1HS subfamily of Long Interspersed Nuclear Elements(LINEs) has retained the ability to jump autonomously in modern humans. Their mobilization in germline—but also some somatic tissues—contributes to human geneticdiversity and to diseases, such as cancer. Here, we present euL1db, the European database of L1HS retrotransposon insertionsin humans (available at http://euL1db.unice.fr). euL1db provides a curated and comprehensive summary of L1HS insertionpolymorphisms identified in healthy or pathological human samples and published in peer-reviewed journals. A key feature of euL1db is its sample-wise organization. Hence L1HS insertionpolymorphisms are connected to samples, individuals, families and clinical conditions. The current version of euL1db centralizes results obtained in 32 studies. It contains >900 samples, >140 000 sample-wise insertionsand almost 9000 distinct merged insertions. euL1db will help understanding the link between L1 retrotransposon insertionpolymorphisms and phenotype or disease.