The reading and writing skills are fundamental skills for life, they guarantee access to information, to social and health services, success in the course of study, but about one in ten children in the world, is affected by dyslexia.
Dyslexia, one of the learning disorders recognized by Italian law 170/2010 (art.1) characterized by severe reading difficulties, it is present in 5-17.5% of the world population, depending on the diagnostic criteria. In Italy the statistical data provided by the surveys of the Ministry of Education speak of percentages of approx 4.9% of pupils with DSA (which also includes other disorders such as dysgraphia, dyscalculia, dysorthography), given that, moreover, it has increased fivefold from 2010 to 2019, when it was 0.9%, therefore it currently affects around 290,000 children and young people.
In 2020, there were around 16,000 university students with DSA certification.
The University of Edinburgh study
Important data therefore, with respect to which the study just published in Nature Genetics volume 54, entitled Discovery of 42 genome-wide significant loci associated with dyslexia, Discovery of 42 genome-wide significant loci associated with dyslexia. (At the link the study in English).
To date, family studies of dyslexia suggest an inheritance of up to 70%, but few convincing genetic markers have been found. The study looked at 51,800 adults (21,513 male, 30,287 female) who reported a diagnosis of dyslexia and 1,087,070 were controls. Genetic investigation has shown that within the human genome there are as many as 42 variants that may be connected to the development of dyslexia disorders. 15 of these variants were already known to medical science, and were associated with various cognitive disorders, 27 are the new ones identified by scientists and researchers at the University of Edinburgh.
The study of the genetic causes of dyslexia has turned out similar between the sexes and genetic covariance was found with many traits, including ambidexterity, but not with neuroanatomical measures of speech-related circuitry.
In addition, the scientists noted the positive genetic correlation between hearing impairment and dyslexia, suggesting that hearing problems at an early age could influence the acquisition of phonological processing skills.
And, further interestingly, the correlations with educational attainment were also not strong, which may reflect how the school adaptations and other types of support that address learning disadvantage.
The identification of genetic risk factors takes on a significant value, not only in fact it promotes a greater understanding of biological mechanisms, but it can also expand diagnostic capabilitiesfacilitating the early identification of individuals prone to dyslexia and co-occurring disorders for specific support.
This is the largest dyslexia genomic association study (GWAS) to date, with 51,800 adults self-reporting a diagnosis of dyslexia and 1,087,070 controls.
On these topics the course Dysgraphia, targeted educational interventions, scheduled from 1 December, curated by Patrizia Casella.
Dyslexia, in Italy the cases at school quintupled (they are 5%) from 2010 to 2019