What Jérôme Lejeune says
« The state of science allows and compels us to say: “the odds are that we should be able to accomplish something useful in the near future.” If we agreed to invest more in the research effort, not only moneywise but also grey matter and human capacities, all hopes would be possible. Unfortunately it is quite common that the investment is used for eradicating the sick rather than fighting the disease”. In research, there should only be one attitude. We don’t know where the road ends? All the more reason not to waste any time. »
Interview with Jérôme Lejeune in Paris-Match, November 1980
Curing genetic intelligence diseases, the same way Jérôme used to try
Curing genetic intelligence diseases, the same way Jérôme used to try Lejeune : myth or plausible future ?
Medical research is the fundamental activity of the Jérôme Lejeune Foundation. It is what Jérôme Lejeune’s objectives were: medical research advances will be key arguments in the defence of these vulnerable patients.
A large part of the scientific efforts of the Jérôme Lejeune Foundation and Jérôme Lejeune Institute is concentrated on research on Down Syndrome. It is from far the most frequent pathology and therefore the advances of medical research in that field are also primordial for the comprehension and treatment of other genetic diseases which affect the intelligence.
The Jérôme Lejeune Foundation, actor in research
In France, the state does not fund research programmes on Down Syndrome.
This is why, the Jérôme Lejeune Foundation, a non-lucrative organisation recognized to be of public utility, is invested in finding a treatment susceptible of curing intellectual disabilities in people with Down Syndrome: curing Down Syndrome is its finality!
The Foundation is developing its own research programmes and is financially supporting the research teams working on the same theme!
In the same spirit it created a biological resource centre, the Biojel BRC, to put specific genetic material at the disposition of researchers all over the world. It also put at their disposition the InterPP programme which studies the interactions between various proteins, amongst which those involved in Down Syndrome.
The objectives of research
Intellectual disability which affects people with Down Syndrome is what constitutes their major handicap. It prevents them from being autonomous and living normally.
The finality of research on Down Syndrome is therefore to manage to find a cure that will improve and then normalize the patient’s intellectual functions. The aim is to find a way to correct the behaviour disorders, to increase social and learning skills and develop their autonomy. However, the ultimate ambition remains to find a treatment that would completely cure intellectual disabilities: that patients may be in full possession of their intelligence and may live as anyone else. For that two types of action are possible: genotypic research and phenotypic research.
Acting on the genotype
The genotype constitutes the whole or a given part of an individual’s genetic composition. Several genes of the chromosomes 21 are candidates for intellectual disability: RCAN (DSCR1), GIRK5, SYNJ1 etc. Amongst these, two coding genes of the enzymes, DYRK1A and CBS, are the objects of two ongoing researches.
Concerning the first of these two genes, the study Tesdad, financially supported by the Foundation and led by Pr. Mara Dierssen’s and Raphaël de La Torre’s team in Barcelona, aims at evaluating the efficiency of the molecule EGCG, gallate epigallocatechin, extracted from green tea. The EGCG molecule is thought to have a role of inhibition in the overexpression of the enzyme DYRK1A, which is proved to participate in the intellectual deficiency of a mice model for Down Syndrome.
The study concerns adult patients with Down Syndrome. For the moment 87 patients have been included in this study. The first results are to be published at the end of the year and the intermediary results are already encouraging. For the CBS gene, the Foundation initiated the research programme CibleS21 in 2004. The aim is to study the role of the gene expressing the CBS enzyme present on the chromosome 21, which is a gene candidate to be fully or potentially the cause of intellectual disability. The results obtained by Pr. Ann Hérault’s team, winner of the Sisley-Jérôme Lejeune Award in 2013, are promising because the mice models for Down Syndrome have indeed demonstrated the role of the CBS gene in memory and learning process disorders. A new phase can therefore be initiated to find therapeutic applications.
Acting on the phenotype
Another lead in research consists in observing the patient’s phenotypes, in this case the occurrence of the anomalies in the central nervous system functioning caused by Down Syndrome. Thus, the clinical research programme ACHTYF was started by the Jérôme Lejeune Institute. This clinical trial is the extension of the Study ENTRAIN led by the Institute and whose results were published in 2012 in PlosOne, an American scientific magazine. Launched in April 2012, ACTHYF is planned to go on for 5 or 6 years. It aims at confirming and evaluating the effectiveness of a treatment based on folic acid and thyroid hormones on the psychomotor development of young children with Down Syndrome.
Besides, the Jérôme Lejeune Institute is taking part in a clinical trial initiated by the laboratory Roche. After having shown the determining role of inhibition of the GABA receptors in improving the cognitive capacities of the model mice for Down Syndrome, Roche is starting a clinical trial to test a molecule moderator of the GABA receptor in Men. Multicentric and international, the trial will involve patients with Down Syndrome of whom half will be aged from 12 to 13 and the other half from 14 to 30.
New leads, new hopes.
The Foundation is at last encouraging new research programmes to be put into place. Speaking of which, every year it discerns the “Sisley-Jérôme Lejeune Award” and two “young Jérôme Lejeune researchers awards”, which aim at promoting therapeutic research on genetic diseases and encouraging young scientists to work precisely in this field of research.
Medical research on genetic intellectual diseases will only move forward if there is a true desire to support scientists and create the necessary conditions for the initiation of new studies. As Sébastien Jacquemert said: “all these new leads demonstrate that we must not give up when faced with children who have cerebral development behavioural disorders, because with the right treatment it may be possible to modify the disorders and re-establish certain functions.”*
* Figaro 06/01/2011, about his work on Fragile-X Syndrome