PRESS RELEASE
NEW HYPERTENSION GENE DISCOVERED
Researchers from the Centre for Genomic Regulation (CRG) have collaborated in the identification of the genetic base of familial hypertension.
The results of their work, published on March 11th in the journal Nature Genetics, conclude that mutations in a gene cause the majority of cases of a rare form of familial hypertension.
This work is the product of genome sequencing in various families affected by this disease and demonstrates the power of genomic medicine and bioinformatics to identify the cause of rare diseases. 
Hypertension is a disease affecting some 10 million people in Spain and 26% of the world population*. In some cases hypertension is hereditary. A group of researchers from the Centre for Genomic Regulation in collaboration with different laboratories in France have discovered which gene is involved in most cases of hereditary hypertension with hyperpotassemia or Gordon's syndrome.
Up to now, the role of two genes involved in this type of hypertension was known, but only explained 10% of cases. Through sequencing the coding section of the genome (the part containing the information for proteins) of two families affected by this ailment, the scientists observed that all of the patients shared mutations on the KLHL3 gene. After extending the study to more families with the same pathology they were able to confirm that KLHL3 was mutated in most cases. Finally, they compared the genomes of these people with others who have sporadic hypertension, i.e., not inherited, demonstrating that the mutations are specific to people with hereditary hypertension with hyperpotassemia.
“Our discovery explains most cases of familial hypertension with high levels of potassium in the blood. Moreover, we observed that the mutations of the KLHL3 gene affect the same pathway as the genes that had previously been described and therefore end up causing the same disease”, explains Daniel Trujillano, one of the researchers who conducted the work from the Genes and Disease laboratory at the CRG. “Thanks to the latest-generation sequencing we can carry out studies like this that allow the discovery of the cause of specific diseases and therefore aid diagnosis," he adds.
“This work demonstrates that the combination of new sequencing technologies and bioinformatic studies are very powerful if applied effectively. Today they have helped to decipher a rare genetic disease, facilitating the diagnosis of such diseases which is often a long and difficult process. For example, in the case of these families, it would have represented more than ten years of research”, adds Xavier Estivill, coordinator of the Genes and Disease programme at the CRG.
The study has allowed the identification of new components of cell signaling pathways, which, from the ionic transport to the kidney, open new possibilities for pharmacological studies of hypertension. “Many of the advances in common diseases affecting a large proportion of the population, as is the case with high blood pressure, come from research into rare diseases, which are the result of observing hereditary transmission, as with the Gordon’s Syndrome. This type of research needs to be boosted, so the benefit can be multiplied”, says Estivill, coordinator of this project and other research studying the genome in different diseases.
The work was carried out in collaboration with the University of Nantes and other French research centres. The researcher Jean-Jacques Schott, principal investigator of the work at the University of Nantes, coordinated this study during his sabbatical year as part of the CRG’s Genes and Disease research programme.
 
** Reference work: 
Louis-Dit-Picard H*, Barc J*, Trujillano D*, et al. KLHL3 mutations cause familial hyperkalemic hypertension by impairing ion transport in the distal nephron. et al. Nat. Genet. (in press). *shared first authorship. 
** Acknowledgements: Catalan Government and the National Research Plan.
 
For further information: Laia Cendrós, Centre for Genomic Regulation (CRG). Tel. +34 93 316 02 37 - Email