Nature Genetics has found a range of DNA variants associated with dyslexia

For the first time, scientists have identified a large number of genes
associated with dyslexia.

Of the 42 gene variants identified, about one-third were previously associated
with general cognitive ability and educational attainment.

The researchers say their findings, published in the journal Nature Genetics, help us understand the biology
behind why some children have difficulty reading or spelling.

Dyslexia is known to occur in families — in part due to genetic factors — but until now, little
was known about specific genes associated with the risk of developing the disease.

The study, led by the University of Edinburgh, is the largest genetic study
of dyslexia to date.
The team said previous studies linking dyslexia to specific genes were conducted in only a small number of families, and the evidence is unclear
.

The latest study involved more than 50,000 adults diagnosed with dyslexia and more than 1 million adults
who were not diagnosed with dyslexia.

The researchers tested the relationship between millions of genetic variants and dyslexia status and found 42 significant variants
.

Some of these are related to other neurodevelopmental conditions, such as language delays, thinking skills, and academic achievement
.
However, many genes are novel, and they may represent genes
more specifically related to the key process of learning to read.

Many of the genes associated with dyslexia are also associated
with attention deficit hyperactivity disorder.
Genes associated with dyslexia overlap in terms of mental illness, lifestyle, and health conditions overlap much less
.

Some associated genetic variants were also significant in one of the Chinese samples, suggesting that there are general cognitive processes
that do not depend on language type in learning to read.

The researchers said they were able to predict reading and spelling skills in children and adults from four other studies, using genetic information from the study, but not with the accuracy
needed for diagnosis.

Other principal investigators involved in the study are from the Max Planck Institute for Psycholinguistics in the Netherlands, the QIMR Berghoff Institute for Medical Research in Australia and 23andMe in
the United States.

Lead researcher Michelle Luciano, from the University of Edinburgh's School of Philosophy, Psychology and Language Sciences, said the study revealed many unanswered questions
about dyslexia.

Dr Luciano said: "Our findings suggest that shared genetic differences affect boys and girls very similarly, and that there is a genetic link
between dyslexia and dual dexterity.
" "Previous studies have suggested that some brain structures may change in people with dyslexia, but we found no evidence
that genes could explain this.
"

"Our findings also suggest that dyslexia is genetically strongly associated with reading and spelling test performance, reinforcing the importance of
standardized testing in identifying dyslexia.
"

Journal Reference:

1. Doust, C.
   , Fontanillas, P.
   , Eising, E.
   et al.
   Discovery of 42 genome-wide significant loci associated with dyslexia.
   Nat Genet, 2022 DOI: 10.
   1038/s41588-022-01192-y